US officials name prime suspect for bomb plot as al-Qaeda expert

US officials say no one has yet claimed responsibility for the plot.
But they have said it bears the hallmarks of al-Qaeda in the Arabian Peninsula (AQAP).
One of the prime suspects is Saudi-born bomb maker Ibrahim Hassan al-Asiri.He is also believed to be behind an attempt to blow up a plane bound for Detroit on Christmas Day last year.
Explosives found on that occasion also contained Pentaerythritol tetranitrate (PETN).
Al-Asiri also helped make another PETN device for a failed suicide attempt against a Saudi Arabia's counter-terrorism chief last year. The official survived
but the attacker died.
US deputy national security adviser, John Brennan, told an American news channel: "AQAP has been outspoken in its determination to carry out attacks. Yes, it certainly points in that direction."