London knife attack comes amid British push to arm more police

A stabbing in a busy London square on Wednesday shook a police force already on "severe" alert following a series of terror-related attacks in Britain and Europe, as a young man killed one American woman and injured five people. 

A 19-year-old Norwegian who emigrated to Britain in 2002, whom police subdued with a stun gun, has been arrested on suspicion of murder. Metropolitan Police officials have said their investigation "increasingly points to this tragic incident as having been triggered by mental-health issues," as Mark Rowley, the assistant commissioner, told reporters. 

"So far we have found no evidence of radicalization or anything that would suggest the man in our custody was motivated by terrorism," Mr. Rowley said, adding that the 10:30 PM attack appeared "spontaneous," with victims randomly selected. 

After a spate of attacks in Europe this summer, including an Afghan teen refugee's axe and knife attack in Würzburg, Germany, in July, many Brits had feared the stabbing would prove to be linked to terrorism. Police had quickly increased police presence around the city, as London Mayor Sadiq Khan encouraged the public to be calm, but vigilant. 

"We all have a vital role to play as eyes and ears for our police and security services and in helping to ensure London is protected," he said.

Most of the country's law enforcement officers are not armed with guns. A key part of the rationale for a lightly armed police force, however, has been the ability to keep British criminals lightly armed, as well. But with European countries on edge following recent attacks, using knives and an axe, guns, and a truck, British law enforcement is adding more weapons to its arsenal.

In the last year, authorities have said they would boost the number of police trained to handle firearms, as The Wall Street Journal reports, a change prompted by concerns after the Paris terror attack. Currently, 2,200 officers in London are trained to carry weapons, with 600 more slated to receive training. By the end of next year, police throughout the country plan for 900 more to receive training, and to station a quarter of those in London. 

"The reality of having to deal with armed and deadly attackers is that you need firearms officers who will use force to stop those attackers in their aim," Metropolitan Police Commissioner Bernard Hogan-Howe said on Wednesday, according to the Journal.

Still, the vast majority of police in Britain will not carry guns. 

"The whole way that we train officers is that the absolute last resort is to use your firearm," Sir Peter Fahy, the chief constable of the Greater Manchester Police, told Public Radio International last year. "When you get into a situation, you assess the situation, you give yourself other options. And it starts from a position, always, that the best weapon is their mouth."

In Manchester, for example, only 209 of the 6,700 officers are armed, PRI reported. The British police can decrease their need for force partly by deploying mental health workers to deal with non-criminal situations, cases where police officers would generally be the first response in the United States. They also added the position of "police community support officer" ten years ago, an officer who has no role other than to strengthen community relations.

Knives, not guns, are used in many murders in Britain. Past attempts to reduce knife violence have included stop-and-search tactics, gang prevention, and targeted youth justice programs, rather than increased police use of force, the BBC reported last year. Mr. Khan has pledged to continue to fight knife crimes as mayor. 

On Wednesday, police used a stun gun to subdue the stabbing suspect, a decision that earned praise from the assistant police commissioner.

"They detained an armed and dangerous man, and resolved it using the minimum necessary force: no shots were fired," Rowley said, according to The New York Times. "We should be proud of them and the British tradition of using the minimum necessary force."

This report includes material from the Associated Press.