British police today carried out raids to probe the murder of a soldier who was butchered and beheaded on a busy London street by two suspected Islamist extremists, as Prime Minister David Cameron vowed the country would remain resolute in its opposition to terrorism.
After chairing an emergency meeting of the high-level COBRA crisis group, Cameron said Britain's communities would unite in condemning yesterday's attack which he described as a "betrayal of Islam".
Cameron, who cut short his visit to Paris, said the terror attack was "deeply shocking" that has "sickened us all".
"What happened yesterday in Woolwich has sickened us all. We have lost a brave soldier," Cameron said, addressing the media outside 10 Downing Street.
"It was an attack on Britain and it was also a betrayal of Islam. There is nothing in Islam that justifies this truly dreadful act," he said.
"This country will be absolutely resolute in its stand against violent extremism and terror. We will never give in to terror – or terrorism - in any of its forms...Confronting extremism is a job for us all," he added.
Anti-terror police forced their way into a flat and shattered the door frame as they raided an address believed to belong to one of the attackers on a Greenwich housing estate.
They also raided an address in Saxilby, Lincolnshire, in connection with the attack.
"We can confirm that the Metropolitan Police executed a search warrant under PACE (Police and Criminal Evidence Act) at an address in Lincolnshire," police said.
"This is in connection with the ongoing investigation into the murder of a man in Woolwich. The Metropolitan Police are not prepared to discuss the matter further at this stage," they said.
Both suspects in the killing were known to security services, senior Whitehall sources have said.
One of the suspects is understood to be 28-year-old Muslim convert Michael Adebolajo, who is believed to be a British citizen of Nigerian descent, according to sources.
He and another man were under arrest in hospital after being shot by police following yesterday's attack in Woolwich.
Shortly after the killing a man, thought to be Adebolajo, was filmed by a passer-by, saying he carried out the attack because British soldiers killed Muslims every day.
Sources said that reports about the men having featured in "several investigations" in recent years - but were not deemed to be planning an attack - "were not inaccurate".
They confirmed one of the suspects was intercepted by police last year while leaving the country.
Cameron has surveyed the scene of the terror attack where the serving soldier was hacked to death.
The hour-long meeting of COBRA, which stands for Cabinet Office Briefing Room A and is the UK's highest crisis response group, was convened after the soldier was brutally killed.
It was attended by senior Cabinet ministers, police and intelligence chiefs to take stock of the security situation in the country.
"There was an operational update from the police and agencies into the on-going investigation and an update from the MOD (ministry of defence) on protective security. There was a discussion about community cohesion.
The strength and unity of response from Muslim community leaders was recognised and commended by ministers and others around the table," a Downing Street statement confirmed.
nsic experts continue to comb the scene of crime at Artillery Place, off John Wilson Street near the Woolwich barracks.
Police raided the house in Greenwich, near Woolwich, and two sisters in their 30s, an older woman, and a teenage boy were "taken away" by the police.
A mother of two is being hailed for her bravery after it emerged she attempted to talk down the terrorists just after he had killed the soldier with a machete.
Ingrid Loyau-Kennett, 48, received a special mention by Cameron in his statement.
"When she was told by one of them (extremists) they wanted to start a war. She replied: 'You're going to lose. It is only you versus many'. She spoke for us all," he said.
Loyau-Kennett, a cub scout leader trained in first aid, put her own life on the line to try and persuade the murderers to hand over their weapons.
"I started to talk to him and I started to notice more weapons and the guy behind him with more weapons as well. By then, people had started to gather around. So I thought OK, I should keep him talking to me before he noticed everything around him," Loyau-Kennett said.
"He said 'I killed him because he killed Muslims and I am fed up with people killing Muslims in Afghanistan they have nothing to do there," she added.
The man killed in the attack has been confirmed as a soldier in the British army from the Woolwich barracks and his family have requested for his identity to not be disclosed at this stage.
Cameron's views were echoed by London mayor Boris Johnson, who blamed the brutal attack by two Nigerian Muslim suspects as a result of the "warped mind-set" of the killers.
"One obvious point, it is completely wrong to blame this killing on Islam but also wrong to draw a link between this murder and British foreign policy," Johnson said.
"The fault lies with the warped mind-set of those who did it and for the sake of the victim and his family the killers need to be brought to justice," he said while visiting Woolwich to appeal for calm.
Labour party leader, Ed Miliband, also spoke of the "appalling murde" that had shocked the world.
"The British people will be horrified by what has happened in Woolwich. They will be united in believing that this terror on our streets cannot be allowed to stand," Miliband said.
"The Labour Party will offer the government our complete support in establishing the facts of what happened and ensuring that those responsible face the full force of British justice," hesaid.
Deputy Prime Minister Nick Clegg said: "The whole nation's thoughts will be with the family and friends of the victim this evening. People across our country, whatever background they are from, will be united in condemning this attack and we will stand together, as we always do, in our response."
It has now been confirmed that the victim was a serving soldier from the army barracks in Woolwich but his identity is being withheld on the request of his family.
The dead soldier – who was wearing a Help for Heroes T-shirt – is believed to be a member of the Royal Regiment of Fusiliers, which is currently based overseas.
He was ambushed by the men as he left the base in Woolwich, who attacked him and then dragged his body into the middle of the road to pose for photographs while standing over him waving a cleaver and a gun, according to eye witnesses.
Floral tributes and messages continue to pour in at the scene of thebrutal murder, with many referring to the victim as a "fallen hero"
Meanwhile, the soldier killed in the attack has been named as Drummer Lee Rigby of the 2nd Battalion the Royal Regiment of Fusiliers.
Drummer Rigby, 25, from Manchester, leaves behind a two-year-old son.
The suspects were known to security services, sources have said.
The victim's name was announced by the Ministry of Defence pending formal police identification