YEMEN SAUDI ARABIA AL QAEDAAn undated handout photo released on 31 October 2010 by the Yemeni Interior Ministry shows Saudi - Arabian Ibrahim Hassan al - Asiri , who tops a Saudi Arabian terrorism list and is the brother of a suicide bomber killed in an attempt to kill Saudi counter - terrorism chief Prince Mohammed bin Nayef last year . According to news reports several U . S . officials said they were increasingly confident that al - Qaida ' s Yemen branch , the group behind the Christmas attack , was responsible for the bombs concealed inside cargo packages and destined for the United States . Investigators were taking a close look at the group ' s bomb making expert , Ibrahim Hassan al - Asiri , who helped make the bomb used in the Christmas attack and another PETN device used against a top Saudi counterterrorism official last year , a U . S . intelligence official said . EPA / YEMENI INTERIOR MINISTRY / HANDOUT EDITORIAL USE ONLY < 뉴스 의 새 시대 , 연합뉴스 Live > < 모바일 애플리케이션 > < 포토 매거진 >< 저작권자 ( c ) 연합뉴스 . 무단 전재 - 재배 포금 지 . >