Ethnic profiling pondered after failed bombing

Passengers could be searched according to their race, ethnic background, age and gender, a decision likely to face opposition from civil rights groups.

Announcing a series of new security measures yesterday, Mr Johnson said passengers would face further delays as more were searched. As well as body scanners, which will be brought in at Heathrow by the end of this month, passengers will see more sniffer dogs.

And by the end of the year all British airports will be required to have trace equipment in place to detect explosives in the air.

In a House of Commons statement, Mr Johnson accepted no one technology would be "100 per cent effective" and acknowledged there were civil liberties concerns about profiling, but said ministers also had an "overriding obligation" to protect lives.

"We are examining carefully whether additional targeted passenger profiling might help to enhance airport security," Mr Johnson said.

"We will be considering all the issues involved, mindful of civil liberties concerns, aware that identity-based profiling has its limitations, but conscious of our overriding obligations to protect peoples' life and liberty."

He added: "It is clear that no one measure will be enough to defeat inventive and determined terrorists and there is no single technology which we can guarantee will be 100 per cent effective against such attacks."

Mr Johnson attempted to play down reports of a rift between the US and Britain over intelligence sharing after Gordon Brown's spokesman disclosed that intelligence about Abdulmutallab was handed to the US before Christmas Day when Umar Farouk Abdulmutallab, a former student at University College London, attempted to ignite explosives packed in his underwear as the plane made its final descent to Detroit.

But Mr Johnson said the information did not suggest any imminent attack. "I would like to clarify that no information was either held by the UK or shared by the UK with the US that indicated Abdulmutallab was about to attempt a terrorist attack against the US."

Director of civil rights group Liberty Shami Chakrabarti said ethnic profiling would be "dangerous, self-defeating and downright irresponsible". She said: "Much can be done to enhance airline security if cost and inconvenience are no object.

"But any nods in the direction of ethnic profiling are dangerous, self-defeating and downright irresponsible. Has no one noticed the terrorists' ability to capitalise on discrimination or the recruits from a range of different backgrounds?

"Whether on the street or at the terminal, suspicious behaviour is a sensible basis for search by policing professionals; race or religion is not."

Shadow home secretary Chris Grayling supported the "prudent measures" to protect passengers but accused the Prime Minister of making false claims over the intelligence about the plot.

He said: "For the Prime Minister to exaggerate, mislead or spin intelligence information, particularly when it relates to a terrorist threat, is absolutely unacceptable behaviour by the man who leads our Government."