A 14-year-old boy was killed when an attacker wielding a sword went on the rampage in north-east London.
Police were called to reports of a car crashing into a house and people being stabbed in Hainault at about 07:00 BST.
The boy was taken to the hospital, where he eventually died.
Four other people, including two police officers, were injured before the suspect, who had been jumping over people’s garden fences, was apprehended and Tasered in a front garden.
The 36-year-old male was arrested, and Metropolitan Police said he was in the hospital being treated for injuries sustained when his vehicle collided with the property.
Watch: Police pursue a sword-stabbing suspect as he climbs over garage rooftops.
According to authorities, his state indicated that he had not yet been interviewed.
Assistant Commissioner Louisa Rolfe stated that their investigations had not revealed any prior contact between the individual and the police.
A man with a long knife was spotted in Laing Close, according to social media footage.
Ch. Supt. Stuart Bell acknowledged there would be “understandably a desire for answers and an explanation as to what happened” and officers were working to “establish the full facts”.
Ch. Supt. Bell said the two Met officers had suffered wounds requiring surgery.
He described the officers’ stab wounds as “significant” but not life-threatening.
The injuries of the two other members of the public were also “not believed to be life-threatening”.
Ch. Supt. Bell said police did not believe there was any ongoing threat to the wider public and they were not seeking any other suspects.
He added that he did not believe it was terror-related and was not a “targeted” attack.
As she ran, the woman called out to another neighbour, a youngster on his way to school, who was then struck by the perpetrator as he turned around, he claimed.
Doorbell footage appears to show the attacker’s van slamming into a building while someone is in its path.
I took him down.
Another eyewitness, Chris Bates, who lives in Thurlow Gardens, said he saw the suspect run through the area.
“He ran through the gardens and came out on to the street by the house next door to me,” he told BBC Radio 5 Live.
“The police were there. He then ran down to two doors down and tried to get on the sort of scaffold, and they Tasered him and took him down.”
Manpreet Singh, who also witnessed the attack, told BBC Radio 5 Live he had walked out of an office when he “heard chaos” on the other side of the road.
“I saw a group of people, five or six of them, trying to fight off a guy—he had a sword in his hand,” he said.
“There were about seven or eight police cars on that road, and after another ten minutes, I noticed the guy running towards the station and entering the road opposite the station.
“He tried to get into one of the houses but couldn’t get into it and that’s when they tapped him.”
Hainault London Underground station was closed during the incident and local buses were diverted.
Ch. Supt. Bell said the boy’s family was being supported by specialist officers at this “unimaginably difficult time”.
Mayor of London Sadiq Khan said: “I’m sure I speak for the entire city when I say our thoughts are with this young child and his family.”
He said additional uniformed officers would be in the area over the coming days and asked residents in Hainault to pass on any footage recorded on phones or doorbell cameras to the police.
Prime Minister Rishi Sunak described the incident as “shocking”, adding: “Such violence has no place on our streets.”
Courageous response
He thanked emergency services for their “courageous response” and praised the officers who risked their lives to defend others as the “best of us.”
Rick Prior, leader of the Metropolitan Police Federation, described the incident as a “sad reminder” of the dangers cops faced in keeping Londoners secure.
“It’s often forgotten by people who attack our profession and the difficult and dynamic decisions that officers are confronted with on an hourly basis that we work with heroes whose courage is incredible,” he said.
The Metropolitan Police corrected the boy’s age to 14 after previously stating that he was 13.