WASHINGTON (AP) - A White House official says it appears to be "an attempted act of terrorism."

Law enforcement and national security officials say a Northwest Airlines passenger from Nigeria tried to blow up the plane as it was landing in Detroit today on a flight from Amsterdam.

They say the man claimed to be acting on al-Qaida's instructions.

Officials say passengers subdued the man and may have prevented him from detonating the explosives as the plane made its approach to Detroit.

An intelligence source says the man is being held and treated at a hospital in Ann Arbor.

A congressman who's the top Republican on the Homeland Security Committee says the suspect is a Nigerian man named Abdul Mudallad.

According to Congressman Peter King, the flight began in Nigeria before stopping in Amsterdam.

A spokeswoman for the Federal Aviation Administration says nothing unusual was reported until the flight was on final approach. She says the pilot then declared an emergency, but landed without incident a short time later.

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