British security agency MI5 was aware that Nigerian bomber Umar Farouk Abdulmutallab, whose attempt to blow up a packed US plane was foiled on Christmas, had "multiple communications" with Islamic extremists in UK three years ago, but did not share this with American officials.
Quoting counter-terrorism officials, The Sunday Times reported that Abdulmutallab was "reaching out" to extremists whom MI5 had kept under surveillance while he was studying at University College, London.
Officials said the 23-year-old Nigerian was "starting out on a journey" in Britain that culminated in his attempt to bring down Northwest Airlines' flight 253 from Amsterdam as it prepared to land in in the US city of Detroit on Christmas Day.
According to the report, British officials have now passed a file to their US counterparts on Abdulmutallab's activities in Britain while he was a student from 2005 to 2008.
It showed his repeated contacts with MI5 targets who were subject to phone taps, e-mail intercepts and other forms of surveillance. Intelligence officials have defended their decision not to flag Abdulmutallab as a possible terrorist risk.
They said he was one of many youths who mix with extremists, but are not themselves thought to be involved in plotting or supporting terrorism.
British officials believe Abdulmutallab was recruited to undertake the Detroit plot after he left Britain, most probably while he was in Yemen last summer.
Up to a dozen young British Muslims are thought to be engaged in terrorist training there, the newspaper said quoting officials.
