DETROIT – A man who claimed to be an agent of al-Qaida was charged Saturday with trying to blow up a Northwest Airlines flight on Christmas Day as it was preparing to land in Detroit, officials said.

The Justice Department said 23-year-old Umar Farouk Abdulmutallab had a device containing a high explosive attached to his body on Flight 253 from Amsterdam. As the flight neared Detroit's airport on Friday, Abdulmutallab set it off — but it sparked a fire instead of an explosion, the government said.

A preliminary analysis of the device shows that it contained PETN, also known as pentaerythritol, according the affidavit filed in federal court in Detroit.

Abdulmutallab allegedly told passengers that his stomach was upset, then pulled a blanket over himself, the affidavit said. Passengers then heard popping noises that sounded like fireworks and smelled smoke before at least one passenger climbed over seats and tackled Abdulmutallab.

"Had this alleged plot to destroy an airplane been successful, scores of innocent people would have been killed or injured," U.S. Attorney General Eric Holder said in a statement. "We will continue to investigate this matter vigorously, and we will use all measures available to our government to ensure that anyone responsible for this attempted attack is brought to justice."

In Nigeria, a prominent banker said he feared that it was his son — a former university student in London who had left Britain to travel abroad — committed the unsuccessful attack.

The father, Alhaji Umaru Mutallab, told The Associated Press on Saturday he didn't know exactly where his son was but planned to speak with Nigerian authorities.

"I believe he might have been to Yemen, but we are investigating to determine that," said the father.

Abdulmutallab claimed to have been instructed by al-Qaida to detonate the plane over U.S. soil, said a U.S. law enforcement official. But others cautioned that such claims could not be verified immediately. Another official said the U.S. had known for at least two years that that the Abdulmutallab could have had terrorist ties and was on a list that includes people with known or suspected ties to a terrorist organization.

All the officials spoke on condition of anonymity because the investigation was continuing.

London's Metropolitan Police also was working with U.S. officials, said a spokeswoman who spoke on condition of anonymity in line with department policy. A search was under way Saturday at an apartment building where Abdulmutallab is said to have lived in a posh West London neighborhood.

University College London issued a statement saying a student named Umar Farouk Abdulmutallab studied mechanical engineering there between September 2005 and June 2008. But the college said it wasn't certain the student was the same person who was on the plane.

The White House said it believed it was an attempted act of terrorism and stricter security measures were quickly imposed on airline travel. The incident was reminiscent of Richard Reid, who tried to destroy a trans-Atlantic flight in 2001 with explosives hidden in his shoes, but was subdued by other passengers.

Intelligence and anti-terrorism officials in Yemen said they were investigating claims by the suspect that he picked up the explosive device and instructions on how to use it in that country. The officials spoke on condition of anonymity because they are not authorized to speak to the media.

Passenger Jasper Schuringa, one of the 278 passengers onboard the Northwest Airlines flight, said Saturday he heard a pop, saw smoke and climbed over seats to stop a man from trying to blow up a Northwest Airlines flight in Detroit.

"I didn't think. I just went over there to try to save the plane," Schuringa, of Amsterdam, told CNN.

Melinda Dennis, another passenger who was seated in the front row of the plane, said the man was brought to the front row and seated near her. She said his legs appeared to be badly burned and his pants were cut off. He was taken off the plane handcuffed to a stretcher, she said.

An intelligence official said he was being held and treated in an Ann Arbor, Mich., hospital. A spokeswoman for the University of Michigan Medical Center in Ann Arbor said one passenger from the flight was taken there, but referred all inquiries to the FBI.

Officials in the Netherlands said an initial investigation showed that routine security procedures were followed at Schiphol Airport in Amsterdam with no irregularities. Abdulmutallab's name was on the passenger manifesto that was forwarded and approved by U.S. authorities before takeoff.

The list that Abdulmutallab's had been on in the U.S. is maintained by the U.S. National Counterterrorism Center and includes about 550,000 names, an official said. People on that list are not necessarily on the no-fly list, and New York congressman Peter King says Abdulmutallab was not on the no-fly list. Dutch anti-terrorism authorities said Abdulmutallab's was traveling on a U.S. visa valid through the first half of 2010.

In response to Friday's incident, some airlines were telling passengers that new U.S. government security regulation prohibit them from leaving their seats an hour before landing.

Air Canada said in a statement that new rules imposed by the Transportation Security Administration limit on-board activities by passengers and crew in U.S. airspace. The airline said that during the final hour of flight passengers must remain seated. They won't be allowed access to carryon baggage or to have any items on their laps.

U.S.-bound travelers were also undergoing body searches at Amsterdam's airport, and passengers flying to the United States from London's Heathrow said they received text messages informing them that the hand baggage allowance had been reduced to one item.

"The extra measures apply worldwide on all flights to the U.S. as of now and for an indefinite period," says Judith Sluiter, spokeswoman for the Dutch National Coordinator for Counterterrorism.

President Barack Obama was notified of the incident and discussed it with security officials, the White House said. Officials said he is monitoring the situation and receiving regular updates from his vacation spot in Hawaii.

Nigeria's information minister, Dora Akunyili, condemned the attempted bombing. She said the government has opened its own investigation into the suspect and will work with U.S. authorities.

"We state very clearly that as a nation we abhor all forms of violence," Akunyili said in a statement issued Saturday.

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Associated Press Writers Corey Williams in Detroit; Lara Jakes in Baghdad; Jon Gambrell in Lagos, Nigeria; Arthur Max in Amsterdam; Jennifer Quinn in London; Ahmed al-Haj in Yemen; and Joan Lowy, Eileen Sullivan, Larry Margasak and Devlin Barrett in Washington contributed to this report.