SKY NEWS: Two attackers filmed their deadly assault on a man in Woolwich, according to Sky sources.
Senior Whitehall sources said the attackers had also asked passers-by to film them, and they shouted "Allahu Akbar" (Allah is great).
Footage shows the men saying: "We swear by almighty Allah we will never stop fighting you".
A meeting of Cobra - the government-level national emergency response committee - has been convened, the source added.
Home Secretary Theresa May has described the events in Woolwich, south east London, as "sickening."
Sky Home Affairs Correspondent Mark White said: “There has been a concern for some considerable time about the potential for home-grown terrorist groups.
“These kind of attacks do not need to be sophisticated and in many respects the less sophisticated they are, the more easily an attack can be perpetrated.” » | Wednesday, May 22, 2013