British spy services under pressure over soldier's murder

Michael Adebolajo, 28, and Michael Adebowale, 22, who remained under armed guard in hospital after being shot by police at the scene, were known to the intelligence services but were reportedly assessed as not posing a deadly threat.

The distraught wife of the murdered soldier Lee Rigby said the family found it hard to accept that the 25-year-old had been killed not in a war zone but on the streets of his own country.

A huge pile of floral tributes was building up outside the barracks in Woolwich, south London, where Rigby was brutally attacked on Wednesday afternoon.

More details emerged about Adebolajo, who was born to devout Nigerian Christians but converted to Islam a decade ago and had attended meetings of the extremist group Al-Muhajiroun, which is now banned in Britain.

He had reportedly sold inflammatory literature at a stall in Woolwich, where his increasingly extremist behaviour in recent weeks had alarmed other Muslims.

Reports said Adebolajo had attempted to travel to Somalia to fight alongside Al-Qaeda-linked Shebab insurgents but had been turned back and had his passport confiscated by police.

He was captured on film shortly after the attack brandishing a bloodied knife and meat cleaver and claiming he had killed the soldier because British forces killed Muslims every day.

Less is known about the other suspect but he is also believed to be of Nigerian origin.

Dramatic footage of the incident on the Mirror newspaper's website also showed Adebolajo charging at a policewoman before he was shot and injured.

As detectives tried to establish how Adebolajo apparently went from an outspoken convert to a killer, the government was forced to defend the security services against criticism they missed signs which might have helped prevent the grisly murder.

A parliamentary committee will look into the role of the security services, but communities minister Eric Pickles said even if the men had been known to intelligence agencies, it was impossible to keep tabs on everyone all the time.

"There is a world of difference between holding extreme views and committing murder," Pickles told BBC TV.

A former senior intelligence officer said it was extremely difficult to detect attacks of the type seen in Woolwich even if the suspects had been known to authorities for years.

Richard Barrett, former head of counter-terrorism at Britain's foreign intelligence service MI6, said: "These people are probably coming out of a small group without, necessarily, any overseas connections or any other broader connections in the United Kingdom which could come to the attention of the security services more than they did.

"To find the signals, the red flags as it were, I think is enormously hard," he told the BBC's Newsnight programme.

The dead soldier's wife Rachel, speaking alongside other family members, said she had been aware of the dangers her husband faced serving in Afghanistan, but added: "You don't expect it to happen when he's in the UK. You think they're safe."

Police released two women they had arrested as part of the investigation on Thursday although a 29-year-old man remained in custody on suspicion of conspiracy of murder.

Omar Bakri Mohammed, the founder of the Al-Muhajiroun movement which was banned in Britain under anti-terror laws, told AFP from Lebanon that he recalled Adebolajo as a "very shy" young man who regularly attended his public talks when the preacher lived in London.

Bakri refused to condemn the soldier's murder. "I don't condemn his actions because he attacked a young British soldier. But I can say to the Muslims in the UK you are not allowed to live among people and then go and kill them because Islam does not permit you."

Faith leaders in Britain joined together to condemn the murder and hailed the cohesion of different religions in response to the atrocity.

Shaykh Ibrahim Mogra, of the Muslim Council of Britain, said it was "a truly barbaric act that has no basis in Islam".

Meanwhile, the Help for Heroes charity for wounded troops experienced a huge surge in donations after it emerged that Rigby had been wearing one of its t-shirts when he was killed.