A plea of "not guilty" was entered on behalf of a Nigerian man accused of attempting to detonate a bomb on a plane bound for Detroit on Christmas Day, at his first court appearance in the United States on Friday.
Umar Farouk Abdulmutallab, 23, declined to enter a plea.
He was indicted on Wednesday by a grand jury on six charges, including the attempted murder of 290 people aboard the plane and attempted use of a weapon of mass destruction.
Wearing leg shackles, he appeared in court in Detroit on Friday, where US Magistrate Mark Randon entered a "not guilty" plea on his behalf. Several of the passengers on the flight were in the courtroom.
Abdulmutallab tried to detonate a bomb on Northwest flight 253 from Amsterdam to Detroit on 25 December, but the plane landed safely after he was overpowered by passengers.
He faces life imprisonment on the charge of attempting to use a weapon of mass destruction. It's expected, however, that he will be offered a plea deal in exchange for information.
The incident has prompted strong criticism of airport security and US intelligence services. The hearing came a day after President Barack Obama issued a report on the incident that said officials had enough information to foil the attack but failed to do so because of a variety of errors.