DETROIT--A passenger on a Detroit-bound Northwest Airlines flight tried to detonate an explosive device that was strapped to his leg and later told investigators that he was trying to blow up the plane and had affiliations with al Qaeda, according to a senior U.S. official.
The passenger was identified by authorities as Abdul Mudallad, a 23-year-old Nigerian national, according to Rep. Peter King, a New York Republican who is the ranking member of the House Homeland Security Committee.
The device was technologically advanced and potentially devastating, Mr. King said. "This was not a firecracker," he said.
Stephanie van Herk, a passenger from the Netherlands who was in seat 18B, said the Northwest plane had lowered its landing gear when she heard a loud bang. At first she thought the plane might have gotten a flat tire, but then she said saw a flame leap from the lap of a man sitting in the row behind her in the window seat, 19A.
"It was higher than the seat," said Ms. van Herk, who was traveling to Detroit on route to a vacation in New York.
"Then everyone started screaming. It was panic," Ms. van Herk, 22 years old, said. She said the flight attendants shouted, "What are you doing? What are you doing?"
Mr. King said the suspect's name did not appear on any of the terrorist watch lists maintained by U.S. authorities, but that the Nigerian national did turn up "hot" in other terrorism-related databases maintained by intelligence officials.
Mr. Mudallad suffered 3rd-degree burns when the device detonated on approach to Detroit, according to Mr. King. He said none of the other passengers was seriously injured.
The man told investigators that he was given the device by al Qaeda operatives in Yemen, where he was also given instructions on how to detonate it, the U.S. official said.
"This guy claims he is tied to al Qaeda, specifically in Yemen," the official said. "He claims he was on orders from al Qaeda in Yemen."
Bill Burton, a White House spokesman, said President Barack Obama, who is vacationing in Hawaii, was notified of the incident after 9 a.m. local time and held two secure conference calls with his national security team to discuss the incident, but that his schedule had not changed.
"The president is actively monitoring the situation and receiving regular updates," Mr. Burton said.
The Department of Homeland Security said in a statement that airline passengers should expect to see additional screening measures put in place on both domestic and international flights.
The senior U.S. official said investigators were still trying to determine whether the suspect's claims of ties to al Qaeda were legitimate and what his motives were. Asked whether the man may have been sent to retaliate against recent U.S.-supported air strikes against al Qaeda targets in Yemen, the official said: "They are interested in finding that out now."
"There's definitely a terrorist nexus -- that's the term being used by the people I'm talking to in Washington," Mr. King said following his briefings Friday. He would not say, however, whether there was a direct link to al Qaeda.
Mr. King said authorities were scrambling to find out where a security breach might have occurred. The plane departed from Lagos, Nigeria, and had a stopover in Amsterdam before flying to Detroit, according to Mr. King. He also said there was no intelligence indicating it was part of a wider plot involving other attempted attacks, but that authorities weren't taking any chances.
One person was taken to the University of Michigan Medical Center and was still hospitalized Friday evening, said hospital spokeswoman Tracy Justice.
Shortly after the plane landed around 11:50 a.m. Detroit time, the Transportation Security Administration put out a statement indicating that "out of an abundance of caution" the jet's passengers were going through a special security screening and the luggage in the hold also was being re-examined.
Authorities were interviewing passengers, even as the plane sat at a remote corner of the airport surrounded by a phalanx of law-enforcement and emergency vehicles.
Once passengers realized the suspect's pants were on fire, they called for water, according to Ms. Van Herk, her sister, Dominique van Herk, and their cousin, Celeste van Herk.
The man was pulling his burning pants down, Stephanie van Herk said. She and several other passengers got water from the galley and the man was doused with water. Then a male Dutch passenger jumped on the perpetrator, Ms. van Herk said.
Once the man was subdued, he was taken to business class and his hands were bound, she said. A few moments later the plane was on the ground, and several security officers boarded the plane and took the suspect away, she said.
Though the plane had Delta markings, it was a Northwest Airlines flight. Northwest is part of Delta after a merger.
Delta said the Airbus 330-300 plane, Flight 253, had 278 passengers aboard and landed safely. The airline said it is cooperating fully with authorities and referred questions to law-enforcement officials.
The additional security measures ordered by TSA could cause further delays to what already has been a difficult and storm-battered holiday travel season for millions of U.S. passengers. More-extensive airport screening procedures, coupled with likely stepped-up verifications of some passenger identities, could complicate post-Christmas travel.
Regardless of what the investigation uncovers about the suspect's motives or the material that ignited, Friday's incident is likely to renew debate over whether additional security systems are necessary to allow flight attendants to alert cockpit crews about cabin emergencies.
In addition to calling pilots on the intercom, airlines and security experts for years have debated the concept of providing cabin crews with additional ways to warn pilots about potential threats from passengers, Video cameras, wireless alerting devices or some type of discreet alarm switch have all been discussed.
So far, the Federal Aviation Administration and many airlines have been resisting such mandates, arguing that they would be expensive and unnecessary.