A man said by Whitehall sources to be a member of the British armed forces has been killed on a busy south London street in what has been described as a terror attack. His exact identity has not been revealed. Follow our live coverage of the day's events here.
Two suspects were shot by armed police after spending several minutes speaking to bystanders and making political statements to camera.
The home secretary says security has been tightened at all London barracks, and the government's emergency response committee Cobra will meet this morning to discuss the attack. David Cameron has cut short his trip to Paris to chair the meeting.
Home Secretary Theresa May has said that while we have seen terrorism on the streets of London before, "we have always stood firm against it - despicable acts like these will not go unpunished", she has promised.
The emergency meeting this morning will be attended by politicians, the UK's most senior police officer and the new head of MI5.
Witnesses yesterday described seeing two men armed with knives and a gun repeatedly assault the victim. One of the men called for Britain to end its involvement in foreign conflicts. The image shown here is from footage taken at the scene.
The two men - who were shot by police - are being held in hospital under armed guard while counter terrorism police wait to question them.
The BBC's Ben Ando, who has been in Woolwich overnight, says it has been a scene of considerable and measured activity. The scene of the killing was on the south circular road - one of London's busiest routes, and forensic teams have worked through the night to complete their work so the road can re-open.
Meanwhile, a tow-truck has removed a vehicle - covered with a red canvas cover - which is thought to have been involved. It is thought the victim was struck by a car before being attacked by the two men, says our correspondent Ben Ando.
Initially, witnesses thought the two men were trying to help the man, but then they realised they were killing him. Lots of amateur footage was recorded at the scene yesterday and police have urged people to send them any video or images they have of the scene.