Updated, 19:08

A MEETING of the UK’s national emergency committee has been called after a man – thought to be a serving British soldier – has been killed, and reportedly decapitated, in a machete attack in London this afternoon.

The man was attacked in Woolwich, in the east of the city.

A Twitter user who claimed to have seen the event said the incident had occurred near a primary school.

He said the victim had been hit by a car, whose occupants had then gotten out of the car and attacked the man with a machete, decapitating him.

He added that armed police officers had then ‘taken out’ one of the attackers who was wielding a machete.

Another had tried to fire a weapon at the police but the firearm backfired, injuring its holder, he said.

ITV News published footage recorded by a passer-by, showing one of the alleged killers – still carrying a machete-style knife, and with his hands bloodied – attempting to justify his actions. (Viewer discretion is advised.)

On Twitter, British prime minister David Cameron said the killing was “truly shocking” and said he had asked the Home Secretary, Theresa May, to convene a meeting of COBRA, the national emergency response team.

London mayor Boris Johnson said the attack was a “sickening, deluded and unforgivable act of violence”.

Sky News said its sources indicated that the killing may have been a politically motivated terrorist attack.

It said the deceased man was wearing a t-shirt for the ‘help for Heroes’, a charity for servicemen and women wounded in British foreign operations since 2001, and quoted the local MP who said the victim was a serving soldier.

One patient was airlifted from the scene while another was removed by ambulance.