Teenager Killed in London Sword Attack, Terrifying Video Shows Suspect Before Arrest

The incident went down on Tuesday morning, after authorities said they responded to reports of a vehicle which had been driven into a house, followed by a series of stabbings in the northeast London neighborhood of Hainault.

A 14-year-old teenage boy was among the victims; he died "shortly after" being taken to the hospital for treatment.

"The child’s family are being supported by specially trained officers. Everyone across the Met is keeping them in our thoughts at this unimaginably difficult time," Metropolitan Police Chief Superintendent Stuart Bell said in a statement, adding, "The events of this morning are truly horrific and I cannot begin to imagine how all those affected must be feeling."

In total, five people were injured in the attack -- three members of the public and two police officers. The other two members of the public are in the hospital, though Bell said "their injuries are not believed to be life-threatening."

The officers, meanwhile, will both require surgery thanks to their "significant injuries," injuries which are also not considered life-threatening.

Per Bell, a 36-year-old man was tasered and arrested 22 minutes after the first call to police; he's currently in custody but has not been named. Video of the man walking around with the sword, interacting with police before he was arrested, has appeared on social media (above).

"I want to reiterate that at present we do not believe there is any ongoing threat to the wider community, we are not looking for more suspects and this incident does not appear to be terror-related," said the police chief.

At this point, authorities say they're "committed" to finding out "why this terrible incident happened."

In a statement, London Mayor Sadiq Khan said he was "absolutely devastated" by the incident, before praising first responders for "running towards danger to protect others."