No Security Threat in New Incident on US Plane

A U.S. law enforcement official says an unruly passenger was detained Sunday when a Northwest Airlines flight landed in Detroit, Michigan, but he was later declared as not a security threat.

The plane was on the same route and carried the same flight number as one on Friday, when a Nigerian man allegedly tried to blow up Northwest Flight 253 just before landing.

In the latest incident, security personnel arrested a passenger upon landing Sunday because he was verbally abusive to the flight crew and had locked himself in the airplane bathroom for a long time.

The pilot radioed for emergency help. Passengers were evacuated and dogs sniffed the luggage which was spread out on the tarmac.

A law enforcement official tells news agencies that the passenger turned out to be a businessman who got sick during the flight.

Airline security had been tightened since Friday, when authorities say 23-year-old Nigerian Umar Farouk Abdulmutallab tried to light an explosive substance that had been strapped to his body. He is now under arrest.

President Barack Obama issued a statement from his vacation in Hawaii Sunday, saying he had been notified of the new incident and stressed the importance of heightened security measures for air travel.

U.S. Homeland Security Secretary Janet Napolitano told (U.S. news network) CNN there is "no indication" that Friday's attempted attack was part of a larger terrorist plot.

In a separate interview with ABC News, Napolitano said it would be inappropriate for her to speculate on whether the suspect, 23-year-old Nigerian Umar Farouk Abdulmutallab, had ties to al-Qaida as he has claimed.

The suspect is listed in a U.S. government intelligence database. But he was not on the "no-fly list" that would ban him from boarding flights headed to the U.S.

White House Press Secretary Robert Gibbs told ABC the incident has prompted officials to review procedures for placing potential terrorists on watch lists, and reevaluate security systems at airports.

A preliminary analysis by the Federal Bureau of Investigation said the suspect was trying to detonate an explosive called PETN. Instead of exploding, the device started a fire and badly burned Abdulmutallab's leg. He was overpowered and detained by other passengers and crew members.

Officials say Abdulmutallab told them he had received training for the attack from al-Qaida operatives in Yemen.

Charges were read against him Saturday in a Michigan hospital where he is being treated for burns.

Officials say Abdulmutallab began his trip in Nigeria. But the Nigerian government says the suspect had been living outside the country for some time.

Nigeria's information minister (Dora Akunyili) told reporters Sunday that Abdulmutallab snuck into the country Thursday, the day before the attack, and left the same day.

Nigerian officials say they have launched their own probe into the incident, and that they are working with U.S. investigators.