The dramatic video emerged after terrified eyewitnesses saw two men shot by police marksmen following a machete attack on a serving soldier in Woolwich, south-east London.
Man tells camera: 'I apologise that women had to witness this today'
Soldier attacked with meat cleavers and knives in Woolwich, SE London
Eyewitness says: 'They were hacking at him, chopping him, cutting him'
Two suspects waited until police arrived before trying to attack them
Prime Minister David Cameron described the killing as 'truly shocking'
Cobra meeting hears there are strong indications it was terrorist incident
Suspects used 'a number of weapons' in attack, Metropolitan Police say
Muslim Council: Act will no doubt heighten tensions on British streets.
A dramatic video tonight emerged of a man with bloodied hands, carrying knives and ranting 'We swear by almighty Allah we will never stop fighting you', after a serving soldier was hacked to death by two men just 200 yards from an Army barracks.
The man can be seen and heard talking to the camera. The video came as terrified eyewitnesses saw two men shot by police marksmen after the machete attack in Woolwich, south-east London.
The two men are thought to have waited around for 20 minutes until Metropolitan Police officers arrived and then tried to attack them - but were swiftly shot by armed policemen, including a woman.
They apparently shouted 'Allahu Akbar', which means 'God is great' in Arabic, and tried to film the attack, the BBC's political editor Nick Robinson said.
Metropolitan Police Commissioner Sir Bernard Hogan-Howe tonight confirmed two men had been arrested and officers from the counter-terrorist unit were leading the investigation into the killing.
He said: 'It is hard to comprehend the shocking and horrific scenes we have seen this afternoon on a busy street as Londoners went about their day as normal. We have launched a murder investigation.'
Theresa May tonight called a meeting of the Government's emergency Cobra committee in response to the machete and knife attack on the man who was wearing a Help for Heroes T-shirt.
The Home Secretary said she had been briefed on the killing by the head of MI5 and police later confirmed they were treating the incident as a possible terror attack.
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The Cobra meeting heard that security has been tightened at Woolwich barracks and increased at all London barracks. It was also told there are strong indications that this was a terrorist incident.
Mrs May said said: ‘What happened today in Woolwich was a sickening and barbaric attack. This attack was an attack on everyone in the UK. It will be condemned by people from every community.
‘We have seen terrorism on the streets of Britain before, and have always stood firm against it. Despicable acts like these will not go un