http://www.bbc.co.uk/news/uk-2266446825 May 2013 Last updated at 10:47 GMT
Woolwich attack: MI5 'offered job to suspect'
Abu Nusaybah: "They (MI5) asked him if he'd be interested in working for them"
MI5 asked Woolwich murder suspect Michael Adebolajo if he wanted to work for them about six months before the killing, a childhood friend has said.
Abu Nusaybah told BBC Newsnight his friend - one of two men arrested after Drummer Lee Rigby's murder in south-east London on Wednesday - had rejected the approach from the security service.
The BBC could not obtain any confirmation from Whitehall sources.
Abu Nusaybah was arrested at the BBC after giving the interview.
Newsnight reporter Richard Watson said after the interview had concluded he left the studio to find officers from the Metropolitan Police counter terrorism unit waiting to arrest Abu Nusaybah.
The Met confirmed a 31-year-old man had been arrested at 21:30 BST on Friday in relation to suspected terrorism offences and search warrants were being executed at two homes in east London.
The arrest was not directly related to the murder of Drummer Rigby, it said.
The soldier was killed in front of dozens of people near Woolwich Barracks, where he was based, on Wednesday afternoon.
Mr Adebolajo and Michael Adebowale, who was also arrested at the scene, remain in hospital after being shot by police.
'Bugging me'
In his Newsnight interview, Abu Nusaybah said he thought "a change" had taken place in his friend after a trip to Kenya last year.
He said Mr Adebolajo had told him he travelled there "to study", but instead, was part of a group rounded up by "Kenyan troops" and interrogated in a prison cell.
During his detention he said he was "beaten quite badly", Abu Nusaybah said, and in his opinion, his friend had also been subjected to sexual abuse, although he was too "ashamed" to say exactly what happened.
Floral tributes have been left at the scene of the killing
After this, he became withdrawn "and less talkative - he wasn't his bubbly self", Abu Nusaybah said, adding: "His mind was somewhere else."
He also said Mr Adebolajo was "stopped" upon his return to the UK from Kenya and was later "followed up by MI5" who were "knocking on his door".
He was "basically being harassed", Abu Nusaybah said.
He added: "His wording was, 'They are bugging me - they won't leave me alone.'
"Initially they wanted to ask him if he knew certain individuals.
"But after him saying that he didn't know these individuals, what he said was they asked him if he would be interested in working for them.
"He was explicit in that he refused to work for them but he did confirm he didn't know the individuals."