In the face of appeasement and denial everywhere in the West, the jihad grows more brazen. Here is the feed from the BBC:
Senior aides to Mayor of London Boris Johnson describe the Woolwich killing as a 'sickening deluded deranged act of violence', says the BBC's Robin Brant.
Senior Whitehall sources have told the BBC that the Woolwich attackers are thought to have tried to film their attack whilst shouting "Allahu Akbar" - God is Great, says political editor Nick Robinson.
The men were said to have been of Muslim appearance.
The Prime Minister is expected to speak to the Home Secretary at 18:15 BST from a train to Paris about what is now being treated by government as a suspected terrorist attack, Mr Robinson says.
Witness Graham Wilders told the BBC he arrived on the scene to find a car crashed into a wall and a man on the ground.
"Two people were lying over him and I thought they were trying to resuscitate him," he said.
But Mr Wilders said he drove on to park his car, and when he returned another witness told him the two men were stabbing the man on the ground.
Prime Minister David Cameron tweets: "The killing in #Woolwich is truly shocking - I have asked the Home Secretary to chair a COBRA meeting."
A crowd standing outside the police cordon Police have closed the area around the crime scene
Police, who have given little information so far, say they will issue an official statement between 17:30 BST and 18:00 BST.
Sources tell the BBC's James Landale Mrs May has also spoken to the Metropolitan Police Commissioner, Bernard Hogan-Howe, and the head of MI5, asking to be updated on the incident.
The Home Secretary Theresa May summons a meeting of Cobra, the government's emergency response committee in Whitehall, to assess the incident in Woolwich.
1718: This eyewitness wishes to remain anonymous
"I was walking my dog and heard some shouting about 50 yards from me. A man was running down the road and being chased by a car. The car then screeched to a halt and two men got out one had some kind of sword. They literally swung at the other guy's head. The armed police turned up and there were some shots. We were told to go home and now they won't let us out. We're in lockdown. There actually now seems more activity than there was before. I can hear helicopters and there are police officers with guns."
A helicopter at the scene Police and ambulance helicopters were sent to the incident
The Ministry of Defence said it was urgently looking at the reports that the incident involved a soldier, but had no further comment.
London Mayor Boris Johnson says his thoughts are with the victims' families.
Ministry of Defence cannot confirm that a serving soldier died in the Woolwich attack.
One witness, identified only as James, said two men attacked another man, aged about 20, who was wearing a Help for Heroes T-shirt.
"These two guys were crazed. They were just animals. They dragged him from the pavement and dumped his body in the middle of the road and left his body there," he told LBC radio.
Police say they are not looking for anyone else in relation to the incident in Woolwich.
Mr Raynsford says police have removed a "substantial number of weapons" from the scene, including knives and at least one firearm.
The Independent Police Complaints Commission (IPCC) confirms it has been informed of the incident.
In a statement, the IPCC says: "Investigators have been deployed to the scene and to the post-incident process."
The incident happened close to Woolwich Barracks, and local MP Nick Raynsford says the dead man was a soldier serving there.
An aerial shot of the crime scene Police have cordoned off the scene to investigate
David Dixon, head teacher at Mulgrave Primary School which is in the area, went out into the street when he heard a disturbance.
"There were lots of police and emergency vehicles etc and I saw a body lying in the road," he said.
"All the traffic had stopped. There were gunshots after that so I'm not sure about the situation after that, but all I needed to know was that there was an emergency and that we needed to go into our emergency procedures and make sure that the children were as safe as possible."
An aerial shot of the crime scene Police have cordoned off the scene in Woolwich
Two injured men have been taken away from the scene, and London Ambulance Service says one is in a "serious" condition.
London Ambulance Service confirms one man was found dead at the scene.
contacted the BBC. He was at the scene. This is what he said: "I got there minutes after it happened because you could hear gun shots from Woolwich high street, basically two men carried out an axe attack on a young army cadet walking along the street, by the looks of things the police responded and then shot them in front of the public, at the same time I couldn't really tell if the cadet was fatally or not hurt as police were crowded around him."
Whitehall officials say the incident in Woolwich is not connected to any intelligence-led operation, BBC security correspondent Frank Gardner reports.
Mr Raynsford tells BBC Radio 5 Live: "What I have heard from both the borough commander and the station commander of the barracks indicate this was a serious incident involving a number of weapons including firearms.
"I am told that one of the individuals involved in the incident... is a soldier serving in the Army in the barracks."
Local MP Mr Raynsford says a soldier serving at a nearby Army barracks has died in the incident.
Local MP Nick Raynsford says one person has been killed in the incident and two others have been seriously injured.
A witness claims two men in a car ran over another man, then got out of the car and attacked him, the BBC's Matt Prodger reports.
It is claimed the victim was wearing a Help for Heroes charity T-shirt, but this has not been confirmed.
Eyewitnesses say two men attacked another man with a "machete-style knife".
Reports also suggests shots were fired, although details are not yet clear.
Local primary school head teacher David Dixon tells the BBC News Channel he saw a body in the road and "there were gun shots after that".
He instructed staff to lock all the gates of his school and an air ambulance landed in the playground.
Most of the children have now gone home. Mr Dixon said everything inside the school was "calm and orderly".
Firearms officers are at the scene and a cordon has now been established.
Posts on Twitter claim one man was attacked with a machete, but police have not confirmed this.
Police said they were called to reports of an "assault".
London Ambulance Service said an air ambulance and four crews were at the scene.
Police say the area around John Wilson Street has been shut down.
Police are responding to reports of a "serious incident" in Woolwich, south London.
Initial reports suggest a man has been attacked, and pictures posted on Twitter appear to show three people lying on the ground.
Scotland Yard said the incident took place in John Wilson Street, at 14:20 BST.