A teenage boy has been killed in a London sword attack. Here's what we know

London’s mayor, Sadiq Khan, said he was "absolutely devastated" about the incident and the UK’s prime minister, Rishi Sunak, described it as "shocking".

A policeman outside the home of a man arrested for a sword attack in Hainault, east London. Source: AAP / Andy Rain

Key Points

• A teenager has been killed in a stabbing attack in London.
• A 36-year-old man has been arrested on suspicion of murder.
• King Charles has paid tribute to those injured and the family of the teenager who was killed.

A murder suspect remains in hospital after a 14-year-old boy was killed and four other people were injured in a stabbing in north-east London that the UK prime minister has called a "shocking incident".

A 36-year-old man was tasered and arrested in Hainault on Tuesday morning, then taken to hospital, after earlier being hurt when his van hit a house.

Police said he had been detained on suspicion of murder.

Police tasered and arrested a man after a stabbing was reported near Hainault in east London. Source: AAP / PA/AP

Four other people were injured in the attack — two police officers who suffered wounds that require surgery, but are not life-threatening, and two members of the public whose injuries are also not thought to be life-threatening.

Chief Superintendent Stuart Bell, of the Metropolitan Police, said he did not believe the incident was a targeted attack, and it was not believed to be terror-related.

"It is with great sadness that I confirm one of those injured, a 14-year-old boy, has died. He was taken to hospital after being stabbed and sadly died shortly afterwards," Bell said.

The sword-wielding suspect was tasered and arrested at the scene but has not yet been interviewed because of his injuries, the Met said.

Representatives of the emergency services speak in Hainault, north east London, where a 14-year-old boy was killed in a sword attack. Source: AAP / Jordan Pettitt

Dramatic footage obtained by the PA news agency captured the suspect being cornered and tasered by officers on a residential driveway.

The video shows how officers shout at the suspect, saying "don't move, don't f---ing move" after he is brought to the ground by three separate taser discharges.

The words "suspect contained" are eventually heard as a female officer pulls the sword away from the attacker.

Footage shared on social media showed a man in the area dressed in a yellow hooded jumper brandishing a large knife in his right hand.

Other footage showed the suspect being chased by police as an officer is heard shouting "lock your doors" as the sword-wielding man entered residential gardens.

A Buckingham Palace spokesman said the King's "thoughts and prayers are with all those affected" by the "horrific" stabbings, adding: "In particular, the family of the young victim who has lost his life."

The force was initially called to reports of a vehicle being driven into a house.

His (King Charles) thoughts and prayers are with all those affected - in particular, the family of the young victim who has lost his life.

Buckingham Palace representative

Metropolitan Police Assistant Commissioner Louisa Rolfe said there has been speculation about the suspect's background, including police contact with him, and "despite urgent and extensive checks today, we have found no trace of a prior incident involving him so far, but we will of course continue to make those inquiries".

A neighbour from nearby Laing Close, who witnessed the attacks, told PA he could "not stop envisioning the boy's face".

"It's quite traumatising now," he said.

UK prime minister Rishi Sunak described the incident as "shocking".

"My thoughts are with those affected and their families," he said.

"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.

"Such violence has no place on our streets."