Bomb suspect believed to be British

The suspect (r) is now thought to be a UK citizen

There have been renewed fears for security on UK flights after police said a man who apparently tried to blow himself up on a Paris-Miami plane was believed to be British.

Metropolitan Police have said they believe the man - identified as Richard Reid - is a UK citizen, but could not confirm that until the immigration authorities have made checks.

I suspect that airport security hasn't quite caught up with that ghastly phenomenon (suicide bombing)

Oliver Letwin, shadow home secretary

Shadow home secretary Oliver Letwin told BBC News on Monday airports had to face up to the new kind of threat posed by suicide bombers.

Charles Shoebridge, a security consultant and former anti-terrorism officer, said: "It could also have happened at Heathrow."

The man, who was arrested after apparently trying to set fire to his shoes on Saturday's American Airlines flight 63, was remanded in custody after appearing in a Boston court on Monday.

He is due to attend a detention hearing later this week.

The Federal Bureau of Investigation has said it is charging Mr Reid, 28, with assault and intimidation of the flight crew.

He was later found to have "two functional explosive devices" in his shoes.

Scotland Yard was contacted by US officials after the man was found to be carrying a UK passport - issued three weeks ago by the British consulate in Brussels - in the name of Richard Colvin Reid, born 1973.

But French police sources have identified him as a Sri Lankan.

There has been some confusion over whether the passport was real, fake or stolen.

Inquiries into the issue of the passport are continuing, and the British consulate in Boston were also due to interview the suspect before his court appearance.

'Acting suspiciously'

The suspect had reportedly been prevented from boarding a similar flight in Paris the previous day because he was acting suspiciously.

Security experts have questioned how he got through airline checks, despite reportedly having detonator wire in his shoes.

Mr Shoebridge said: "Detonators are normally metal, and one would have hoped they would have been detected as he passed through the metal detector.

"If the same metal detectors are in use at Heathrow, which perhaps do not detect down to the floor, or perhaps if a non-metal detonator was used... he would have avoided detection."

Security checks

Mr Shoebridge said there could have been a "breakdown" in the human security chain leading up to flight - which could also happen at a UK airport.

Mr Shoebridge said police tended to get called, and if they decided there was no risk, after checks, the airline staff would defer to their judgement.

"They feel they've done their job in alerting the police - certainly that's the case in this country," he said.

Mr Letwin said it threw up questions about security and nationality.

"As we discovered on 11 September, there are now people who are trying to do very great damage to our society who are willing to kill themselves in the process.

"I suspect that airport security hasn't quite caught up with that ghastly phenomenon."

He said that the "pretty creaky" method of issuing passports would be even more difficult to address.

"The immigration and nationality department officials strive mightily, but... it's not at the moment operating very efficiently.

"But actually I suspect airport security is the first port of call here rather than the passports."