Forensics officers are seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Forensics officers are seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Forensics officers stand near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic officer walks near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Blood stains are seen on the pavement next to an evidence marker after reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic officer walks in the city centre after reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

An evidence marker is seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble TPX IMAGES OF THE DAY

A forensic officer walks in the city centre after reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic worker investigates at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic worker investigates at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic worker investigates at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic worker investigates at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic worker investigates at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A forensic worker investigates at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Police officers and a forensic worker are seen at the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A police officer is seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A knife lies on the pavement after being recovered by the police from a drain following reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A police officer stands near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Police officers stand near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A knife lies on the pavement after being recovered by the police from a drain following reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A broken glass bottle is seen near an evidence marker after reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A police officer patrols a cordon in the city centre after reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A police officer is seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

A police officer is seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Police tape and police officers are seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Police tape and police officers are seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Police cars are seen near the scene of reported stabbings in Birmingham, Britain, September 6, 2020. REUTERS/Phil Noble

Israeli policemen search a man in Jerusalem's Old City following a suspected stabbing attack, according to Israeli police, August 17, 2020 REUTERS/Ammar Awad

A member of medical emergency personnel stands next to Israeli Border police officers as they secure an entrance to Jerusalem's Old City following a suspected stabbing attack, according to Israeli police August 17, 2020 REUTERS/Ammar Awad

Israeli medical emergency personnel treat and evacuate a woman that was injured following an incident including a suspected stabbing attack, according to Israeli police, in Jerusalem's Old City August 17, 2020 REUTERS/Ammar Awad

Israeli security personnel secure an entrance to Jerusalem's Old City following a suspected stabbing attack, according to Israeli police August 17, 2020 REUTERS/Ammar Awad

A woman holds a candle and placard as she takes part in a candlelight vigil at the same location where one year ago Italian carabinieri Mario Cerciello Rega was stabbed to death, in Rome, Italy July 24, 2020. REUTERS/Yara Nardi

People take part in a candlelight vigil at the same location where one year ago Italian carabinieri Mario Cerciello Rega was stabbed to death, in Rome, Italy July 24, 2020. REUTERS/Yara Nardi

People take part in a candlelight vigil at the same location where one year ago Italian carabinieri Mario Cerciello Rega was stabbed to death, in Rome, Italy July 24, 2020. REUTERS/Yara Nardi

Flowers and candles are seen during a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Family members of James Furlong, one of the three victims of the stabbing attack, attend a vigil in their memory, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Family members of the victims comfort each other during a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Bishop of Reading Olivia Graham gives a reading during a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Lord Lieutenant of Berkshire James Puxley speaks during a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Chief Constable of Thames Valley Police, John Campbell speaks during a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Chief Constable of Thames Valley Police, John Campbell and Britain's Home Secretary Priti Patel attend a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Britain's Home Secretary Priti Patel lights a candle during a vigil in memory of David Wails, Joseph Ritchie-Bennett and James Furlong, the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Family members of James Furlong, one of the three victims of the stabbing attack, attend a vigil in their memory, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Britain's Secretary of State for Business, Energy and Industrial Strategy, Alok Sharma and Home Secretary Priti Patel attend a vigil in memory of the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Britain's Secretary of State for Business, Energy and Industrial Strategy, Alok Sharma, Home Secretary Priti Patel and Mayor of Reading David Stevens speak following a vigil in memory of the victims of a stabbing attack, in Reading, Britain, June 27, 2020. Steve Parsons/Pool via REUTERS

Police vehicles are seen parked near the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

Police officers stand near the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

A police officer stands guard near a forensic tent at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

Police officers stand near the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

A police officer stands behind a tape used at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

Flowers are pictured placed near the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

Flowers are pictured placed near the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 27, 2020. REUTERS/Russell Cheyne

Steve Johnson, Assistant Chief Constable for Local Policing West, speaks to reporters at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 26, 2020. REUTERS/Russell Cheyne

Steve Johnson, Assistant Chief Constable for Local Policing West, speaks to reporters at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 26, 2020. REUTERS/Russell Cheyne

Special police forces walk at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 26, 2020. REUTERS/Russell Cheyne

A forensic officer works at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 26, 2020. REUTERS/Russell Cheyne

A view of the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 26, 2020. REUTERS/Russell Cheyne

Emergency services gather at the scene of reported multiple stabbings at West George Street in Glasgow, Scotland, Britain June 26, 2020. REUTERS/Russell Cheyne