Three dozen Americans have converted to Islam in prison and have travelled to Yemen for possible terrorist training with al-Qaeda, raising alarm among U.S. officials. The American administration is on heightened alert because of the potential threat from extremist carrying U.S. passports and the challenge is in detecting and stopping home-grown operatives, according to a new report by the Senate Foreign Relations Committee. These new moves of al-Qaeda profiled by the committee come as U.S. has designated Yemen-based Al Qaeda in Arabian Peninsula (AQAP) as a terrorist organisation and slapped sanctions on its leaders. Two top leaders of the AQAP Nasir al-Wahishi and Said al-Shihri too have been designated as terrorists by U.S. Secretary of State Hillary Clinton, the State Department said. The U.S. is also approaching the U.N. Security Council to slap sanctions on AQAP and its leaders. Despite some heavy blows, al-Qaeda is not on the run, U.S. law enforcement officials told the committee. They said that al-Qaeda has expanded its recruitment efforts to attract non-traditional followers and adopt its operation to new environment. Several of these new recruits have then dropped off the radar for weeks at a time and continue to carry U.S. passports and this radicalisation of individuals has alarmed officials. The report said al-Qaedas recruitment pattern has changed from recruiting militants amongst Arabs, Afghans and Pakistanis and the group is now seeking to recruit American citizens to carry out terrorist attacks in the U.S., West and outside. The document says there is also concern about another group of 10 Americans in Yemen who have converted to a fundamentalist form of Islam and married Yemeni women. A top U.S. intelligence official referred to these men as blond-haired, blue-eyed types fitting the profile of Americans that al-Qaeda would like to recruit. In a letter accompanying the report, the committees chairman Senator John Kerry said these groups seek to recruit American citizens to carry out terror attacks in the U.S. Al-Qaeda forces in Yemen have emerged as a threat to the U.S. by the failed Christmas bombing of a U.S. airliner in Detroit and the shooting spree by a Muslim Army Major in Fort Hood Texas base.