A London university has rejected claims that a man accused of trying to blow up a US plane was radicalised while there.
Malcolm Grant, provost of University College London (UCL), said such reports about Umar Farouk Abdulmutallab were "spectacular insinuation".
Prof Grant has ordered a review of the 23-year-old's time at the university.
Nigerian-born Mr Abdulmutallab allegedly tried to detonate a bomb on a flight as it came into land in Detroit, with 280 people on board.
He is at the centre of a terror investigation on both sides of the Atlantic.
On Wednesday, it emerged the US was aware "a Nigerian" in Yemen was being prepared for a terrorist attack.
Mr Abdulmutallab flew from Lagos to Amsterdam before changing planes for a flight to Detroit. He allegedly attempted to ignite explosives stored in his underpants as Northwest Airlines Flight 253 made its final descent.
'Wider malign impact'
Mr Abdulmutallab took an engineering with business finance degree at UCL between September 2005 and June 2008, and was president of its Islamic society between 2006 and 2007.
In an opinion piece on the Times Higher Education website, the provost hit out at reports Mr Abdulmutallab had helped organise a "war on terror" conference two years ago.
In his article, Mr Grant condemned the attempted airline attack, saying had it succeeded, it would have been "an act of terrorism causing mass murder on an appalling scale".
But he said there was no evidence to suggest the suspect was radicalised at UCL.
Announcing a full independent review of Abdulmutallab's time at UCL, he said if any evidence emerges of "a wider malign impact on him or by him, we shall certainly take appropriate action".
He also condemned reports suggesting UCL was "complicit" in the radicalisation of Muslim students and failed to prevent extremists from giving lectures on campus.
Mr Grant referred to a recent incident when an Islamic preacher, Abu Usama, who has "views considered abhorrent by many", was invited to speak at the UCL union.
"Once the wider issues around his views became known, the invitation was swiftly withdrawn by the students and the event did not take place," he said.
But Mr Grant insisted the university would continue to guarantee freedom of speech to visiting speakers.
"There is a narrow line that we must walk between securing freedom of speech on the one hand and safeguarding against its illegal exercise on the other, such as in the incitement of religious or racial hatred," he said.
"There is nothing unique in this for universities."
Police in the UK have been searching several London properties linked to the suspect, who was on a UK watch-list.
Mr Abdulmutallab was refused a visa in May and placed on a security list after he applied to study at a bogus college.