People stand under a provincial flag at half mast prior to a procession for Royal Canadian Mounted Police (RCMP) Constable Heidi Stevenson, who was shot dead by a gunman the previous day, at Dr. William D. Finn Centre for Forensic Medicine in Dartmouth, Nova Scotia, Canada on April 20, 2020. REUTERS/John Morris

Two individuals in a car glance at the Atlantic Denture Clinic, where the gunman responsible for a mass shooting, Gabriel Wortman, worked, in Dartmouth, Nova Scotia, Canada April 20, 2020. REUTERS/John Morris

An individual walks by the Atlantic Denture Clinic, where the gunman responsible for a mass shooting, Gabriel Wortman, worked, in Dartmouth, Nova Scotia, Canada April 20, 2020. REUTERS/John Morris

A Halifax Police Cruiser monitors the Atlantic Denture Clinic, where the gunman responsible for a mass shooting Gabriel Wortman worked, in Dartmouth, Nova Scotia, Canada April 20, 2020. REUTERS/John Morris

A vehicle drives by as a Halifax Police Cruiser monitors the Atlantic Denture Clinic, where the gunman responsible for a mass shooting Gabriel Wortman worked, in Dartmouth, Nova Scotia, Canada April 20, 2020. REUTERS/John Morris

Two individuals walk by the Atlantic Denture Clinic, where the gunman responsible for a mass shooting, Gabriel Wortman, worked, in Dartmouth, Nova Scotia, Canada April 20, 2020. REUTERS/John Morris

Archie Paray, the gunman and former security guard who held in hostage dozens inside a mall, shakes hand with his former colleague after releasing his hostages in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Hostages are seen released out of the mall where gunman and former security guard Archie Paray held them captive in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Dozens of hostages are released after being held inside a mall by a gunman and former security guard Archie Paray in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Archie Paray, the gunman and former security guard who held dozens in hostage inside a mall, speaks to the public after releasing the hostages in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Archie Paray, the gunman and former security guard who took dozens hostage inside a mall, is arrested by police in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Archie Paray, the gunman and former security guard who took dozens hostage inside a mall, is arrested by police in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Archie Paray, the gunman and former security guard who took dozens hostage inside a mall, is arrested by police in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Archie Paray, a gunman and former security guard, surrenders and releases dozens of hostages outside a mall in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Archie Paray, a gunman and former security guard, surrenders and releases dozens of hostages outside a mall in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez TPX IMAGES OF THE DAY

A gunman who has taken hostage at least a dozen people shows a grenade on a video call with a policeman, witnessed by members of the media outside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Members of the Special Weapons and Tactics (SWAT) team stand by outside the mall where a gunman has taken hostage dozens, in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

A police officer holds a phone where the gunman and hostage-taker of at least a dozen is on a video call inside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

The gunman who has taken hostage dozens show their situation on video call with a policeman, as witnessed by members of the media outside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Journalists talk to a gunman who has taken hostage dozens inside a mall via a walkie-talkie and a video call with a policeman, in San Juan, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

The gunman who has taken hostage dozens show their situation on video call with a policeman, as witnessed by members of the media outside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

A gunman who has taken hostage at least a dozen people shows a grenade on a video call with a policeman, witnessed by members of the media outside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

A gunman who has taken hostage at least a dozen people shows a grenade on a video call with a policeman, witnessed by members of the media outside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

A gunman who has taken hostage at least a dozen people shows a grenade on a video call with a policeman, witnessed by members of the media outside a mall in San Juan City, Metro Manila, Philippines, March 2, 2020. REUTERS/Eloisa Lopez

Zekeriya Altug, Muslim Coordination Council spokesman, Burhan Kesici, Chairman of the Islamic Council for the Federal Republic of Germany, and Aiman Mazyek, leader of Germany's Central Council of Muslims, attend a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Zekeriya Altug, Muslim Coordination Council spokesman, attends a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Burhan Kesici, Chairman of the Islamic Council for the Federal Republic of Germany, attends a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Aiman Mazyek, leader of Germany's Central Council of Muslims, attends a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Aiman Mazyek, leader of Germany's Central Council of Muslims, attends a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Federal Attorney General at the Federal Court of Justice Peter Frank speaks during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Federal Attorney General at the Federal Court of Justice Peter Frank speaks during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer, Justice Minister Christine Lambrecht, Chief Commissioner of Germany's Federal Crime Office (BKA) Holger Muench and Federal Attorney General at the Federal Court of Justice Peter Frank address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer and Justice Minister Christine Lambrecht address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer looks on during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer looks on during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Chief Commissioner of Germany's Federal Crime Office (BKA) Holger Muench looks on during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Chief Commissioner of Germany's Federal Crime Office (BKA) Holger Muench gestures during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer and Justice Minister Christine Lambrecht address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Justice Minister Christine Lambrecht speaks during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer and Justice Minister Christine Lambrecht address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer, Justice Minister Christine Lambrecht, Chief Commissioner of Germany's Federal Crime Office (BKA) Holger Muench and Federal Attorney General at the Federal Court of Justice Peter Frank address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer speaks during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer and Justice Minister Christine Lambrecht arrive to address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer looks on during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Justice Minister Christine Lambrecht speaks during a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

German Interior Minister Horst Seehofer, Justice Minister Christine Lambrecht, Chief Commissioner of Germany's Federal Crime Office (BKA) Holger Muench and Federal Attorney General at the Federal Court of Justice Peter Frank address a news conference two days after a gunman killed 11 people in Hanau, including himself, in Berlin, Germany, February 21, 2020. REUTERS/Fabrizio Bensch

Police officers are seen outside the house of the suspected gunman, following a shooting in Hanau, near Frankfurt, Germany, February 20, 2020. REUTERS/Kai Pfaffenbach

Police officers are seen outside the house of the suspected gunman, following a shooting in Hanau, near Frankfurt, Germany, February 20, 2020. REUTERS/Kai Pfaffenbach

A Palestinian gunman holds a weapon during the funeral of Palestinian Yazan Abu Tabekh, who was killed during an Israeli raid, in Jenin in the Israeli-occupied West Bank February 6, 2020. REUTERS/Mohamad Torokman

An unidentified man brandishes a gun during a protest against a new citizenship law outside the Jamia Millia Islamia university in New Delhi, India, January 30, 2020. REUTERS/Danish Siddiqui SEARCH "PICTURE DELHI PROTESTS" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY

Lynn and Christopher McDonnell, the parents of seven-year-old Grace McDonnell, grieve near Sandy Hook Elementary after learning their daughter was one of 20 school children and six adults killed after a gunman opened fire inside the school in Newtown, Connecticut, U.S., December 14, 2012. Picture taken December 14, 2012. REUTERS/Adrees Latif/File Photo SEARCH "POY DECADE" FOR THIS STORY. SEARCH "REUTERS POY" FOR ALL BEST OF 2019 PACKAGES. TPX IMAGES OF THE DAY.

Palestinians react as a gunman fires a weapon in the air during the funeral of Islamic Jihad militant Abdullah al-Belbasi, in the northern Gaza Strip November 13, 2019. REUTERS/Mohammed Salem

The gunman delivers a message to the camera before beginning an attack on a synagogue in Halle, Germany October 9, 2019 in this still image taken from the gunman's helmet camera video stream.

Holes are seen in the synagogue's door after the gunman’s failed attempts to shoot and detonate it open in Halle, Germany, October 9, 2019 in this still image taken from the gunman's helmet camera video stream.

Apparent explosives cache is seen in a bag inside the vehicle used by a gunman in an attack on a synagogue in Halle, Germany October 9, 2019 in this still image taken from the gunman's helmet camera video stream.

Members of Ukrainian special operation forces take part in an operation to detain a man who reportedly was shooting and threatened to blow up a bridge across the Dnipro River, in Kiev, Ukraine September 18, 2019. REUTERS/Valentyn Ogirenko