A 14-year-old boy died on Tuesday after a man wielding a sword stabbed the youth, two police and two other people, in a street attack in east London, police said.
The man used what appeared to be a Samurai-type sword in the Hainault district shortly before 7:00 am (0600 GMT).
Police said they arrested a 36-year-old man using Taser stun weapons and took him into custody. The incident is not believed to be terror-related, they said.
Chief Superintendent Stuart Bell, from London's Metropolitan Police, said all five victims were taken to hospital.
The two police officers were awaiting surgery for "significant" injuries, he added. But they, and those sustained by the two members of the public, were not believed to be life-threatening.
"It's with great sadness that one of those injured in this incident... has died from their injuries," he told reporters at the scene.
"He was taken to hospital after being stabbed and sadly died a short while after."
Bell called the incident "truly horrific" and said specialist officers were supporting the boy's family.
Prime Minister Rishi Sunak called the stabbings "shocking". "Such violence has no place on our streets," he added in a post on X, formerly Twitter.
"I'd like to thank the emergency services for their ongoing response, and pay tribute to the extraordinary bravery shown by police on the scene."
Video footage and photographs posted on social media appeared to show a man in a yellow jumper on the streets near houses with the weapon.
Emergency service vehicles, including police, fire and ambulances, were seen behind cordons, including near the town's underground railway station.
- Hiding -
One resident, who asked not to be named, said she hid behind a window while the suspect was outside her home shouting "do you believe in God?" at police.
"We were very scared and trying to hide and not show ourselves through the window because he was standing right next to our house and he could have seen us if he looked up," she added.
"We were very scared and we didn't know what to do."
Another witness said he saw two police chasing the man, shouting at him to put down the weapon.
Police in England, Scotland and Wales are not routinely armed but do carry Taser weapons to disable suspects.
London Mayor Sadiq Khan said he was "absolutely devastated" by the incident and was in close contact with the city police commissioner.
"The police offices and emergency services showed the best of our city -- running towards danger to protect others and I thank them from the bottom of my heart," he said.
Last week, Sunak criticised the mayor's record on knife crime in the British capital.
According to official statistics, knife crime increased in London by 20 percent in 2023, with 14,577 offences -- one percent lower than pre-pandemic levels in the year to March 2020.
In England and Wales as a whole, there was a seven-percent increase in knife crime to 49,489 offences, with most (29 percent) in metropolitan areas, the Official for National Statistics said.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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