Yemeni officials have confirmed that Umar Farouk Abdulmutallab spent time in Yemen just before the attempted Christmas Day attack and that he studied Arabic at a local language institute.
His roommate, Ahmed Hassan, told The Associated Press on Wednesday that the Nigerian would sometimes disappear from the suite they shared without any explanation.
Special Report: The Christmas Day Terror Attack
One of the teachers at the institute, Ahmed Mohammed, says Abdulmutallab spent the last 10 days of the holy month of Ramadan sequestered in a mosque and attended barely four hours of the 20-hour course he enrolled in.
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