Terrorism fears prompt second incident on US-bound plane

A flight from Amsterdam to Detroit requested emergency assistance for a disruptive passenger on Sunday, two days after an attempted terrorist attack aboard the same flight, dpa reported.

The Nigerian passenger was questioned by investigators in Detroit after he reportedly spent more than an hour in the plane's restroom, and became "verbally disruptive" when flight attendants questioned him, CNN reported. No explosives were found on the man and he deemed not to be a threat.

But the incident came amid a heightened alert after another Nigerian man allegedly attempted to set off an explosive device on Christmas Day aboard the same flight after spending time assembling the device in the lavatory. Police removed and screened all luggage aboard the plane.

US President Barack Obama was informed of the latest incident, a White House statement said.

"The president stressed the importance of maintaining heightened security measures for all air travel," said spokesman Bill Burton.

Umar Farouk Abdulmutallab, 23, has been charged with attempting to destroy the Northwest Airlines plane carrying 278 passengers on Friday.

ABC News reported Sunday that the attack was planned by al-Qaeda in Yemen, where Abdulmutallab was trained for terrorism, and that the bomb was built there.

Al-Qaeda in the Arabian Peninsula released a written statement Sunday saying, it would seek revenge for a December 17 airstrike on its training camp, according to the Washington-bsed Intel Center, which monitors terrorist groups.

"We shall avenge, God willing, the blood of innocent Muslim women and children," the statement said.

   Abdulmutallab is believed to have smuggled the pentaerythritol (PETN) material on board sometime on the way from Lagos, Nigeria to Detroit via Schiphol airport in Amsterdam. He claimed he had connections to the terrorist network al-Qaeda and terrorist groups in Yemen, The New York Times reported.

He had boarded the plane in Amsterdam and tried near the end of the nine-hour-flight to detonate the explosive as the plane approached the Detroit airport. The device's detonator reportedly malfunctioned, and an alert Dutch passenger jumped on Abdulmutallab to extinguish the flames.

The attempted attack led to heightened security at airports worldwide over the weekend.

In interviews on Sunday television programmes, Secretary of Homeland Security Janet Napolitano said additional security had been put in place "literally within an hour" of the incident.

"One thing I would say to the traveling public over this holiday season, as they return home, is to get to the airport a little bit earlier, because there will be some additional measures," she told NBC's Meet the Press programme. She said measures would be different at each airport to avoid be predictable.

   Passengers told broadcasters that they were newly forbidden to leave their seats or have blankets and pillows in the final hour of the flight. Other reports said that the GPS systems often displayed on viewing screens in passenger planes were shut off to deny passengers orientation about the progress or position of the plane.

   Abdulmutallab's father in Nigeria, a former government minister and bank official, said he had tipped the US embassy six months ago about suspicions he had about his son, Nigeria's newspaper ThisDay reported.