NEW : Doku Umarov says he directed the January 24 airport bombing . NEW : The U.S. has identified a new group of al Qaeda in North Africa that is believed to be behind an attack on a Tunisian resort last month and may have been involved in other recent attacks against Western targets. 36 people were killed in the blast .
NEW : Doku Umarov says he directed the January 24 airport bombing . NEW : He promises more attacks in the future . 36 people were killed in the blast .