A pharmacy shop sign is seen in Valletta, Malta May 22, 2018. REUTERS/Darrin Zammit Lupi

Flowers lie at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Flowers lie at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yeterday, local media reported. REUTERS/Andrew Yates

Flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside , local media reported. REUTERS/Andrew Yates

Flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Flowers lie at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 6, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside yesterday, local media reported. REUTERS/Andrew Yates

Merseyside Police Chief Constable Jon Murphy speaks during a news conference at police headquarters in Liverpool, Britain October 5, 2015. Police Constable David Phillips was killed after being struck by a stolen car during a pursuit of suspected burglars in Merseyside, police confirmed on Monday. REUTERS/Andrew Yates

Liverpool Police Chief Constable Jon Murphy speaks during a news conference at police headquarters in Liverpool, Britain October 5, 2015. Police Constable David Phillips was killed after being struck by a stolen car during a pursuit of suspected burglars in Merseyside, police confirmed on Monday. REUTERS/Andrew Yates

Police forensic officers work at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

A police officer reacts after laying flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

A police officer lays flowers at the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

Police forensic officers work at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

A forensic officer photographs the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

Police vehicles attend the scene at Wallasey Dock Road where a police officer was struck and killed by a car in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

A police forensic officer examines the scene near to where a car involved in the death of a police officer was abandoned in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

Police forensic officers examine the scene near to where a car involved in the death of a police officer was abandoned in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

Police forensic officers examine the scene near to where a car involved in the death of a police officer was abandoned in Wallasey, Britain October 5, 2015. A police officer was hit and killed by a stolen car during a pursuit of suspected burglars in Merseyside, local media reported. REUTERS/Andrew Yates

A police officer looks on as a suspect (R) is handcuffed after they attempt to break into a house belonging to a police officer couple, in the south of Johannesburg, August 12, 2015. Local media reported a rise in robbery and housebreaking incidents in Johannesburg. Picture taken August 12, 2015. REUTERS/Siphiwe Sibeko

A man passes a safe deposit building on Hatton Garden in central London. Burglars are believed to have broken into the Hatton Garden Safe Deposit company over the Easter weekend, local media reported. April 7, 2015. REUTERS/Neil Hall

A sign is displayed outside a safe deposit building on Hatton Garden in central London April 7, 2015. Burglars are believed to have broken into the Hatton Garden Safe Deposit company over the Easter weekend, local media reported. REUTERS/Neil Hall

A police forensic officer walks to a safe deposit building on Hatton Garden in central London April 7, 2015. Burglars are believed to have broken into the Hatton Garden Safe Deposit company over the Easter weekend, local media reported. REUTERS/Neil Hall

A police officer leaves a safe deposit building on Hatton Garden in central London April 7, 2015. Burglars are believed to have broken into the Hatton Garden Safe Deposit company over the Easter weekend, local media reported. REUTERS/Neil Hall

A police officer leaves a safe deposit building on Hatton Garden in central London April 7, 2015. Burglars are believed to have broken into the Hatton Garden Safe Deposit company over the Easter weekend, local media reported. REUTERS/Neil Hall

A police forensic officer enters a safe deposit building on Hatton Garden in central London April 7, 2015. Burglars are believed to have broken into the Hatton Garden Safe Deposit company over the Easter weekend, local media reported. REUTERS/Neil Hall

Markus Kaarma (L), charged with deliberate homicide in the death of 17-year-old Diren Dede of Hamburg, Germany, arrives with his attorney Paul Ryan at the Missoula County Courthouse in Missoula, Montana December 4, 2014. Opening statements began on Thursday in the trial of a Montana man who has admitted to fatally shooting a German exchange student he believed to be a burglar, in a case hinging on what constitutes justifiable use of a gun in self-defense. REUTERS/Arthur Mouratidis (UNITED STATES - Tags: CRIME LAW)

Markus Kaarma, charged with deliberate homicide in the death of 17-year-old Diren Dede of Hamburg, Germany, arrives with his legal team before the opening of court inside the Missoula County Courthouse in Missoula, Montana December 4, 2014. Opening statements began on Thursday in the trial of a Montana man who has admitted to fatally shooting a German exchange student he believed to be a burglar, in a case hinging on what constitutes justifiable use of a gun in self-defense. REUTERS/Arthur Mouratidis (UNITED STATES - Tags: CRIME LAW)

South African goalkeepers Senzo Meyiwa (L) and Itumeleng Khune look on at the end of their international friendly soccer match against Spain at Soccer City in Johannesburg, in this November 19, 2013 file picture. South Africa soccer captain Senzo Meyiwa was shot dead by burglars as he tried to protect his girlfriend, actress and singer Kelly Khumalo, during a break-in. The 27-year-old goalkeeper was hit by a single round in the chest as he confronted two intruders on the night of October 26, 2014 at Khumalo's home in Vosloorus, and was pronounced dead on arrival at hospital. REUTERS/Siphiwe Sibeko/Files (SOUTH AFRICA - Tags: SPORT SOCCER CRIME LAW OBITUARY)

Students use computers to study at Elswood Secondary School in Cape Town November 7, 2013. Even the metal grills welded into its walls did not deter burglars from ripping out the copper cables that delivered Internet to the students of this tough neighbourhood. But Elswood's pupils were saved by alternative technology - free wireless connection via unused TV spectrum known as white space. It's being provided by a consortium including Google as part of a wider trial. Elsewhere in the country Microsoft is operating similar pilots. Both are racing to fine tune a technology that could ultimately bring cheap broadband to the entire continent. Picture taken November 7, 2013. To match Feature AFRICA-INTERNET/ REUTERS/Mike Hutchings (SOUTH AFRICA - Tags: EDUCATION BUSINESS SCIENCE TECHNOLOGY)

Students use computers to study at Elswood Secondary School in Cape Town November 7, 2013. Even the metal grills welded into its walls did not deter burglars from ripping out the copper cables that delivered Internet to the students of this tough neighbourhood. But Elswood's pupils were saved by alternative technology - free wireless connection via unused TV spectrum known as white space. It's being provided by a consortium including Google as part of a wider trial. Elsewhere in the country Microsoft is operating similar pilots. Both are racing to fine tune a technology that could ultimately bring cheap broadband to the entire continent. Picture taken November 7, 2013. To match Feature AFRICA-INTERNET/ REUTERS/Mike Hutchings (SOUTH AFRICA - Tags: EDUCATION BUSINESS SCIENCE TECHNOLOGY)

Students use computers to study at Elswood Secondary School in Cape Town November 7, 2013. Even the metal grills welded into its walls did not deter burglars from ripping out the copper cables that delivered Internet to the students of this tough neighbourhood. But Elswood's pupils were saved by alternative technology - free wireless connection via unused TV spectrum known as white space. It's being provided by a consortium including Google as part of a wider trial. Elsewhere in the country Microsoft is operating similar pilots. Both are racing to fine tune a technology that could ultimately bring cheap broadband to the entire continent. Picture taken November 7, 2013. To match Feature AFRICA-INTERNET/ REUTERS/Mike Hutchings (SOUTH AFRICA - Tags: EDUCATION BUSINESS SCIENCE TECHNOLOGY)

Students use computers to study at Elswood Secondary School in Cape Town November 7, 2013. Even the metal grills welded into its walls did not deter burglars from ripping out the copper cables that delivered Internet to the students of this tough neighbourhood. But Elswood's pupils were saved by alternative technology - free wireless connection via unused TV spectrum known as white space. It's being provided by a consortium including Google as part of a wider trial. Elsewhere in the country Microsoft is operating similar pilots. Both are racing to fine tune a technology that could ultimately bring cheap broadband to the entire continent. Picture taken November 7, 2013. To match Feature AFRICA-INTERNET/ REUTERS/Mike Hutchings (SOUTH AFRICA - Tags: BUSINESS SCIENCE TECHNOLOGY)

Superstar bond fund manager Jeffrey Gundlach, whose collections of art, pricey watches and fine wine were recently plundered by burglars, prepares for a news conference to announce rewards for the return of the items in Los Angeles, California September 24, 2012. The overall value of the property taken from Gundlach's home in the coastal town of Santa Monica, near Los Angeles, two weeks ago was placed at more than $10 million, including a red Porsche Carrera 4S sports car the thieves apparently drove away in. The bulk of the massive heist consisted of paintings by Jasper Johns, who last year won the Presidential Medal of Freedom, the late Dutch abstract artist Piet Mondrian and several others. REUTERS/Jonathan Alcorn (UNITED STATES - Tags: BUSINESS CRIME LAW)

Superstar bond fund manager Jeffrey Gundlach, whose collections of art, pricey watches and fine wine were recently plundered by burglars, arrives for a news conference to announce rewards for the return of the items in Los Angeles, California September 24, 2012. The overall value of the property taken from Gundlach's home in the coastal town of Santa Monica, near Los Angeles, two weeks ago was placed at more than $10 million, including a red Porsche Carrera 4S sports car the thieves apparently drove away in. The bulk of the massive heist consisted of paintings by Jasper Johns, who last year won the Presidential Medal of Freedom, the late Dutch abstract artist Piet Mondrian and several others. REUTERS/Jonathan Alcorn (UNITED STATES - Tags: BUSINESS CRIME LAW)

Superstar bond fund manager Jeffrey Gundlach, whose collections of art, pricey watches and fine wine were recently plundered by burglars, conducts a news conference to announce rewards for the return of the items in Los Angeles, California September 24, 2012. The overall value of the property taken from Gundlach's home in the coastal town of Santa Monica, near Los Angeles, two weeks ago was placed at more than $10 million, including a red Porsche Carrera 4S sports car the thieves apparently drove away in. The bulk of the massive heist consisted of paintings by Jasper Johns, who last year won the Presidential Medal of Freedom, the late Dutch abstract artist Piet Mondrian and several others. REUTERS/Jonathan Alcorn (UNITED STATES - Tags: BUSINESS CRIME LAW)

Superstar bond fund manager Jeffrey Gundlach, whose collections of art, pricey watches and fine wine were recently plundered by burglars, conducts a news conference to announce rewards for the return of the items in Los Angeles, California September 24, 2012. The overall value of the property taken from Gundlach's home in the coastal town of Santa Monica, near Los Angeles, two weeks ago was placed at more than $10 million, including a red Porsche Carrera 4S sports car the thieves apparently drove away in. The bulk of the massive heist consisted of paintings by Jasper Johns, who last year won the Presidential Medal of Freedom, the late Dutch abstract artist Piet Mondrian and several others. REUTERS/Jonathan Alcorn (UNITED STATES - Tags: BUSINESS CRIME LAW)

People make transactions at the ATM machines outside bank branches in central Athens May 24, 2012. Police say that gangs who may have once eyed "hard targets", - like the banks themselves, or jewelers - are now going after homes of ordinary people, where there is far less risk and often large stashes of cash freshly withdrawn from savings accounts. REUTERS/John Kolesidis (GREECE - Tags: POLITICS BUSINESS CRIME LAW)

A man makes a transaction at an ATM machine outside a bank branch in central Athens May 24, 2012. Police say that gangs who may have once eyed "hard targets", - like the banks themselves, or jewelers - are now going after homes of ordinary people, where there is far less risk and often large stashes of cash freshly withdrawn from savings accounts. REUTERS/John Kolesidis (GREECE - Tags: POLITICS BUSINESS CRIME LAW)

A 12 year-old boy shields his face as he leaves Manchester magistrates' court after admitting burglary, during the recent riots in Manchester, northern England August 11, 2011. Prime Minister David Cameron, facing a defining crisis of his premiership, promised on Thursday to crack down on street gangs as a national priority and said rioters behind Britain's worst violence in decades would be hunted and punished. REUTERS/Nigel Roddis (BRITAIN - Tags: CIVIL UNREST SOCIETY POLITICS CRIME LAW)

A 12 year-old boy (R) shields his face as he leaves Manchester magistrates' court with his mother after admitting burglary, during the recent riots in Manchester, northern England August 11, 2011. Prime Minister David Cameron, facing a defining crisis of his premiership, promised on Thursday to crack down on street gangs as a national priority and said rioters behind Britain's worst violence in decades would be hunted and punished. REUTERS/Nigel Roddis (BRITAIN - Tags: CIVIL UNREST SOCIETY POLITICS CRIME LAW)

A police officer guards a house in Salford, northern England June 23, 2011. A man, said by media to be a suspected burglar, was stabbed to death during a break-in at a house in Salford, police said on Thursday. Greater Manchester Police said officers were called to the house in the Pendlebury area of the city just before midnight on Wednesday. REUTERS/Phil Noble (BRITAIN - Tags: CRIME LAW)

Police officers guard a house in Salford, northern England June 23, 2011. A man, said by media to be a suspected burglar, was stabbed to death during a break-in at a house in Salford, police said on Thursday. Greater Manchester Police said officers were called to the house in the Pendlebury area of the city just before midnight on Wednesday. REUTERS/Phil Noble (BRITAIN - Tags: CRIME LAW)

A police officer guards the scene where the body of a man was found in Salford, northern England June 23, 2011. A man, said by media to be a suspected burglar, was stabbed to death during a break-in at a house in Salford, police said on Thursday. Greater Manchester Police said officers were called to the house in the Pendlebury area of the city just before midnight on Wednesday. REUTERS/Phil Noble (BRITAIN - Tags: CRIME LAW)

Police officers guard the scene where the body of a man was found in Salford, northern England June 23, 2011. A man, said by media to be a suspected burglar, was stabbed to death during a break-in at a house in Salford, police said on Thursday. Greater Manchester Police said officers were called to the house in the Pendlebury area of the city just before midnight on Wednesday. REUTERS/Phil Noble (BRITAIN - Tags: CRIME LAW)

Police officers stand in front of the Government House after the presentation of new patrol cars and equipment for the Federal Police in Buenos Aires March 14, 2011. From affluent suburbs to the slums next door, residents live with burglar alarms, iron window grates and a growing fear of violent crime in the urban sprawl that fringes Argentina's capital. Argentines used to be proud of their country's reputation for safety in a notoriously violent region, but things have changed dramatically. Picture taken March 14, 2011. REUTERS/Enrique Marcarian (ARGENTINA - Tags: CIVIL UNREST CRIME LAW POLITICS ELECTIONS)

Argentine President Cristina Fernandez de Kirchner stands next to Police Chief Enrique Capdevila (2nd L) during the presentation of new patrol cars and equipment for the Federal Police in Buenos Aires March 14, 2011. From affluent suburbs to the slums next door, residents live with burglar alarms, iron window grates and a growing fear of violent crime in the urban sprawl that fringes Argentina's capital. Argentines used to be proud of their country's reputation for safety in a notoriously violent region, but things have changed dramatically. Picture taken March 14, 2011. REUTERS/Enrique Marcarian (ARGENTINA - Tags: CIVIL UNREST CRIME LAW POLITICS ELECTIONS IMAGES OF THE DAY)

Argentine President Cristina Fernandez de Kirchner sits in a fire-fighting vehicle during the presentation of new patrol cars and equipment for the Federal Police in Buenos Aires March 14, 2011. From affluent suburbs to the slums next door, residents live with burglar alarms, iron window grates and a growing fear of violent crime in the urban sprawl that fringes Argentina's capital. Argentines used to be proud of their country's reputation for safety in a notoriously violent region, but things have changed dramatically. Picture taken March 14, 2011. REUTERS/Enrique Marcarian (ARGENTINA - Tags: CIVIL UNREST CRIME LAW POLITICS ELECTIONS)

Argentine President Cristina Fernandez de Kirchner (C) heads the presentation of new patrol cars and equipment for the Federal Police alongside Chief Police Enrique Capdevila (R), Superintedent Juan Martinez (L) and Security Minister Nilda Garre (R back) in Buenos Aires March 14, 2011. From affluent suburbs to the slums next door, residents live with burglar alarms, iron window grates and a growing fear of violent crime in the urban sprawl that fringes Argentina's capital. Argentines used to be proud of their country's reputation for safety in a notoriously violent region, but things have changed dramatically. Picture taken March 14, 2011. REUTERS/Enrique Marcarian (ARGENTINA - Tags: CIVIL UNREST CRIME LAW POLITICS ELECTIONS)

Argentine President Cristina Fernandez de Kirchner heads the presentation of new patrol cars and equipment for the Federal Police in Buenos Aires March 14, 2011. From affluent suburbs to the slums next door, residents live with burglar alarms, iron window grates and a growing fear of violent crime in the urban sprawl that fringes Argentina's capital. Argentines used to be proud of their country's reputation for safety in a notoriously violent region, but things have changed dramatically. Picture taken March 14, 2011. REUTERS/Enrique Marcarian (ARGENTINA - Tags: CIVIL UNREST CRIME LAW POLITICS ELECTIONS)

Police officers stand in front of the Government House after the presentation of new patrol cars and equipment for the Federal Police in Buenos Aires March 14, 2011. From affluent suburbs to the slums next door, residents live with burglar alarms, iron window grates and a growing fear of violent crime in the urban sprawl that fringes Argentina's capital. Argentines used to be proud of their country's reputation for safety in a notoriously violent region, but things have changed dramatically. Picture taken March 14, 2011. REUTERS/Enrique Marcarian (ARGENTINA - Tags: CIVIL UNREST CRIME LAW POLITICS)

A man (R) who pulled out a gun on a public bus tries to run after being captured by security guards in Guatemala City February 15, 2011. Robberies on buses are a daily occurrence in Guatemala, according to the GAM (Grupo de Apoyo Mutuo), an organization that monitors human rights abuses. Twenty-four passengers were killed and 110 injured while using public buses last year, according to GAM. REUTERS/Daniel LeClair (GUATEMALA - Tags: TRANSPORT CRIME LAW)

Prosecutor Magdalena Eichinger waits for the begin of the trial against a policeman in a courtroom Korneuburg March 10, 2010. A 14-year-old burglar was shot dead by the policeman after he broke into a supermarket and police arrived to arrest him. REUTERS/Heinz-Peter Bader (AUSTRIA - Tags: CRIME LAW)

Judge Manfred Hohenecker checks his watch before the trial against a policeman in Korneuburg March 10, 2010. A 14-year-old burglar was shot dead by the policeman after he broke into a supermarket and police arrived to arrest him. REUTERS/Heinz-Peter Bader (AUSTRIA - Tags: CRIME LAW)

Files and a law book are placed on the judge's desk in a courtroom before the begin of the trial against a policeman in Korneuburg March 10, 2010. A 14-year-old burglar was shot dead by the policeman after he broke into a supermarket and police arrived to arrest him. "Waffengebrauchsgesetz" reads "weapon use law". REUTERS/Heinz-Peter Bader (AUSTRIA - Tags: CRIME LAW)

Prosecutor Magdalena Eichinger arrives in a courtroom for the trial against a policeman in Korneuburg March 10, 2010. A 14-year-old burglar was shot dead by the policeman after he broke into a supermarket and police arrived to arrest him. REUTERS/Heinz-Peter Bader (AUSTRIA - Tags: CRIME LAW)

Judge Manfred Hohenecker arrives in a courtroom for the trial against a policeman in Korneuburg March 10, 2010. A 14-year-old burglar was shot dead by the policeman after he broke into a supermarket and police arrived to arrest him. REUTERS/Heinz-Peter Bader (AUSTRIA - Tags: CRIME LAW)

Awais Hussain (C), son of Munir Hussain, flanked by his family's solicitor Razi Shah (L) speaks to the media outside the High Court in London January 20, 2010. A businessman who was jailed for savagely attacking burglars who broke into his home and threatened his family was freed on Wednesday. Munir Hussain 53, had been sentenced to 30 months for grievous bodily harm with intent after he hit Walid Salem with a cricket bat in September 2008. But at the Appeal Court, Lord Chief Justice Lord Judge, and two other judges overturned the sentence, replacing it with a two-year suspended term, the Press Association reported. REUTERS/Andrew Winning (BRITAIN - Tags: CRIME LAW SOCIETY)