DETROIT: Hobbled by leg irons, a young Nigerian accused of trying to blow up a US plane on Christmas Day pleaded not guilty during his first court appearance amid heightened security.

Umar Farouk Abdulmutallab, 23, spoke softly from the dock on Friday to confirm his name, how it was spelt and his age. His expression flat, his eyes averted from the gathered crowd, he said he understood the six charges against him.

His court-appointed lawyer, Miriam Siefer, entered the plea of not guilty to all six charges, including attempted murder of 290 people on board the plane and trying to use a weapon of mass destruction. He faces life imprisonment if convicted.

“At this time our client would like to enter a plea of not guilty,” Siefer said, but added, “We have — with our client’s consent — consented to detention.” Abdulmutallab, son of a prominent Nigerian banker, was arrested after the botched Al-Qaeda plot, in which explosives allegedly stitched into his underwear failed to detonate aboard a Northwest flight from Amsterdam to Detroit.

He was badly burnt when the device sparked a fire. Asked if he had taken any medication in the past 24 hours, he said “Yes. Painkillers,” holding his hip.

Legal experts believe this case will last for months. “There are so many agencies - with initials you know and

initials you don’t - involved in a case that transcends territorial boundaries,” said attorney James Thomas, who represented one of four North African immigrants in a 2003 terror trial in Detroit.