A French gendarmerie helicopter prepares to take off from the site after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarmerie helicopter takes off from the site after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarmerie helicopter takes off from the site after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French Army helicopter takes off from the site after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Army helicopters take off from the site after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area near the Gendarmerie Nationale building after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area near the Gendarmerie Nationale building after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French soldiers are seen in a French Army helicopter after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Interior Minister Gerald Darmanin talks to journalists in front of the municipal police offices after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes and firefighters stand near a gendarmerie helicopter after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Interior Minister Gerald Darmanin talks to journalists in front of the municipal police offices after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Interior Minister Gerald Darmanin arrives at the municipal police offices after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Interior Minister Gerald Darmanin removes his protective face mask before a news conference after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Interior Minister Gerald Darmanin talks to journalists after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French Interior Minister Gerald Darmanin talks to journalists after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French soldiers stand near a French Army helicopter after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes stand in front of the municipal police after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French special police forces and firefighters are seen after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French special police forces and firefighters are seen after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarme secures the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes and firefighters stand near a gendarmerie helicopter after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarme stands near a gendarmerie helicopter after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarme secures the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarme secures the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A French gendarme secures the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

A gendarmerie helicopter flies over the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

Journalists work as French gendarmes secure the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

French gendarmes secure the area after an assailant stabbed and badly wounded a policewoman in La Chapelle-sur-Erdre, western France, May 28, 2021. REUTERS/Stephane Mahe

Israeli rescue personnel work at the scene of a stabbing incident in Jerusalem May 24, 2021. REUTERS/Ammar Awad

A police officer works in the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

President of French Ile-de-France region Valerie Pecresse walks towards members of the media at the cordoned-off area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

President of French Ile-de-France region Valerie Pecresse speaks to members of the media at the cordoned-off area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Members of the media stand behind a police cordon near the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

French judicial investigating police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

French judicial investigating police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

A police officer stands guard in the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

A police officer stands guard in the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

Police officers secure the area where an attacker stabbed a female police administrative worker, in Rambouillet, near Paris, France, April 23, 2021. REUTERS/Gonzalo Fuentes

A young woman is stabbed in the leg during a scuffle at a demonstration to mark the informal cannabis holiday, 4/20, in Hyde Park, London, Britain, April 20, 2021. REUTERS/Tom Nicholson

A girl who was stabbed in the leg during a scuffle receives aid at a demonstration to mark the informal cannabis holiday, 4/20, in Hyde Park, London, Britain, April 20, 2021. REUTERS/Tom Nicholson

Police officers give aid to a girl who was stabbed in the leg during a scuffle at a demonstration to mark the informal cannabis holiday, 4/20, in Hyde Park, London, Britain, April 20, 2021. REUTERS/Tom Nicholson

Police officers give aid to a girl who was stabbed in the leg during a scuffle at a demonstration to mark the informal cannabis holiday, 4/20, in Hyde Park, London, Britain, April 20, 2021. REUTERS/Tom Nicholson

A girl is stabbed in the leg during a scuffle at a demonstration to mark the informal cannabis holiday, 4/20, in Hyde Park, London, Britain, April 20, 2021. REUTERS/Tom Nicholson

A West Vancouver Police officer tapes off a crime scene where police said multiple people were stabbed by a suspect who was later taken into custody at a public library in the Lynn Valley neighbourhood of North Vancouver, British Columbia, Canada March 27, 2021. REUTERS/Jennifer Gauthier

First responders work at a crime scene where police said multiple people were stabbed by a suspect who was later taken into custody at a public library in the Lynn Valley neighbourhood of North Vancouver, British Columbia, Canada March 27, 2021. REUTERS/Jennifer Gauthier

A first responder works at a crime scene where police said multiple people were stabbed by a suspect who was later taken into custody at a public library in the Lynn Valley neighbourhood of North Vancouver, British Columbia, Canada March 27, 2021. REUTERS/Jennifer Gauthier