Mr Obama said the system for placing potential terrorists on travel security lists will be fully investigated after a record of Umar Farouk Abdulmutallab, 23, who set off a device on the Amsterdam to Detroit flight was created only last month in the worldwide intelligence community’s central database of information on known and suspected international terrorists.

Last night the same flight suffered another terrorist scare after a passenger -- a Nigerian man -- locked himself in the toilet. Reports said the man had become verbally disruptive after Northwest Airlines Flight 253 landed and was being held in police custody. Officials said the latest man to be arrested posed no security risk. A Delta spokeswoman says all 256 passengers were safely taken off the plane.

The latest incident is likely to heighten fears that air travellers to the US will face delays as they undergo extra security checks. Passengers travelling from UK airports were warned to expect “additional security checks” and limits on hand baggage.

It emerged yesterday that Abduluttalab’s father, Alhaji Umara Mutallab, a former chairman of the country’s First Bank in Nigeria, had visited the US Embassy in Abuja to discuss concerns about his son’s religious beliefs, but a US official said there was not enough negative data to put him on a “no-fly” list or a “selectee” list which calls for mandatory additional security checks.

An inquiry into how Abdulmutallab was able to get the explosive substance PETN, also known as pentaerythritol, onto the aircraft will also take place. According to an affidavit filed in support of the criminal complaint, Abdulmutallab had a device attached to his body when he boarded in the Netherlands on Christmas Day and as flight 253 approached Detroit Metropolitan Airport, Abdulmutallab was said to have set off the device, which resulted in a fire and what appears to have been an explosion.

He claimed he received training and instructions from al Qaeda operatives in Yemen, according to US law enforcement officials, and it has emerged the terrorist group warned of an attack four days before.

In the video posted on extremist websites affiliated with al Qaeda, a bearded man in a head-dress, identified as Mohammed al-Kalwi, says: “We are carrying a bomb to hit the enemies of God.”

Detectives in London yesterday scaled down their search of the apartment where he lived while studying mechanical engineering at University College London, a course he finished last year.

Abdulmutallab later went travelling and the UK declined his fresh visa request after he applied for a course at a bogus college.

Abdulmutallab has been moved from hospital, where he was receiving treatment for burns, to a secure location in Michigan.

Glasgow and Edinburgh airports, which have daily New York flights, posted advice for travellers on their websites, telling them to expect “additional security checks”, though a Glasgow Airport spokesman refused to reveal what they are.

Transport Secretary Lord Adonis said: “Security and police investigations are continuing on both sides of the Atlantic and enhanced security measures remain in force. We will confirm arrangements for the immediate future as soon as we are in a position to do so.”

Abdulmutallab is charged with attempting to destroy the aircraft on its final approach to Detroit airport on Christmas Day and with placing a destructive device on the aircraft.

Eyewitness accounts said he went to the aircraft’s bathroom for around 20 minutes. When he returned to his seat, he said that he had an upset stomach and pulled a blanket over himself.

This was followed by popping noises similar to firecrackers and some reported seeing Abdulmutallab’s trouser leg and the inner wall of the aircraft on fire.

He was overpowered by passengers, including filmmaker Jasper Schuring, 32, who has been hailed a hero, and cabin crew who used blankets and fire extinguishers to put out the flames.



Bomber nicknamed ‘the Pope’ at school due to his piety

A former teacher of the man who tried to blow up a transatlantic airliner said he defended the Taliban in the classroom.

Mike Rimmer taught a teenage Umar Farouk Abdulmutallab history for three years at the British School of Lome in Togo, west Africa.

Though he called him a “model student” and said he had been “expecting great things” from Abdulmutallab, he also recalled one particular lesson when he voiced his views.

He said: “He was always very religious and some of the things he said I thought were a bit over the top. For example, in 2001 we had a number of class discussions about the Taliban and all the other Muslim kids in the class thought they were just a bunch of nutters, but Umar spoke in their defence. I thought maybe he was playing devil’s advocate, trying to keep the class discussion going.

“Often he would stay behind after the lesson or he’d collar me when I was on playground duty and we’d discuss what was going on in the news -- and now he is the news.”

Mr Rimmer also recalled how Abdulmutallab was nicknamed “The Pope” at the boarding school, “because he was so pious.

He added that the “very personable boy” could have gone into politics and “could have become Nigerian president.”

The teacher, who says he took the pupil on school trips to Ghana and London, was contacted by him in 2006 when he said he was going to Yemen to study Arabic.

He said: “At the time I had not heard that it was a hotbed of al-Qaeda, and I just thought he was being adventurous.”

It has also been reported that Abdulmutallab’s father had voiced concerns to US officials about his son last month.

The banker approached the US embassy in Abuja in November, according to reports.

US sources have confirmed a file was opened, according to reports, but say the information did not warrant placing the accused on a “no-fly” list.


‘Safety should override passenger concern about body scans’

The attempted bombing of a US airliner demonstrates once again that al-Qaeda is determined to strike the far enemy and that civil aviation remains one of its favoured targets. It seeks to exploit the inherent security vulnerabilities of air travel and hopes to gain huge international publicity and create a climate of fear.

As with Richard Reid’s failed attempt to blow up an American Airlines’ flight in December 2001, using a bomb hidden in his shoe, Abdulmutallab’s alleged unsuccessful effort was a new variation in sabotage bombing tactics. He attempted to initiate an explosion using a syringe and chemicals strapped to his leg.

The US Transportation Security Administration has the task of protecting American civil aviation. It has reacted swiftly to the Detroit incident. All passengers flying to a US airport will be required to undergo an additional search of hand luggage and a “pat down” body search, and will be restricted to one piece of hand luggage. Once on board they will have to stay seated for the last hour of the flight. Airlines have also been instructed to stop showing in-flight maps displaying the location of the aircraft and the distance to its destination.

These restrictions may help, but they are already causing considerable delays in all airports providing flights to the US, and they are not a panacea.

Some key prerequisites for enhanced security are not visible to the passengers. Most important of all there must be better coordination between intelligence agencies and aviation security management. Umar Farouk Abdulmutallab was known by intelligence agencies to be in contact with jihadi extremists. Why was he allowed to have a US visa and board a flight to the US?

A crucial mistake in the US and other major aviation countries has been the failure to update the technology to keep ahead of the tactics of terrorists. Most airports still lack the sophisticated full-body image scanners that could detect terrorists with explosive substances hidden in body orifices. Flight safety should override passenger sensitivity about body scans. This equipment would considerably improve safety and would help reduce delays which cause such inconvenience and frustration to passengers.

In combination with shared intelligence, these measures would reduce the danger of carnage in the skies.

Paul Wilkinson is Emeritus Professor of International Relations at the University of St Andrews.