Civil Liberties campaigners have accused airport chiefs of sneaking in mandatory fingerprinting of passengers on domestic routes without proper consultation. Heathrow Airport has quietly introduced compulsory fingerprinting and photographic profiling of passengers on domestic routes, including to Glasgow and Edinburgh, ahead of the opening of its fifth terminal late next month.

The move has already caused disquiet among some passengers who were handed leaflets warning they would be barred from their flights unless they co-operated.

Anti-ID card campaigners have demanded to know why no public announcement was made and fear compulsory fingerprinting is smoothing the path for the controversial scheme's introduction UK-wide.

The British Airports Authority (BAA), which operates Heathrow, claims the profiling is needed because the new terminal will have a single departure lounge for domestic and international travellers.

The Home Office wants to prevent travellers from bypassing stringent immigration checks by swapping flight tickets once they are through the initial check-in process.

The new scheme works by passengers giving their print and photograph as they pass through X-ray equipment, before their details are verified using the information when they reach their flight's boarding gate.

Dr Gus Hosein, of the London School of Economics who has studied the impact of technology on civil liberties, claimed the government is "softening up" people, particularly the young, by making fingerprinting appear acceptable in the run up to ID cards.

Hosein, who compared the scheme to those run by the Nazis as part of the Jewish persecution, said: "It's abhorrent and completely unnecessary to introduce this technology in a so-called democratic society.

"This is not how we treat people. I was brought up to believe the only time they will be fingerprinted are criminals.

"Britain is the first country in the democratic world to introduce this scheme as mandatory for flights within its borders. There would be a revolution if it happened in the US.

"What the UK government has been doing over the past decade, and particularly in the last six years, is desensitising people to the idea of being fingerprinted.

"Labour is the only party in the UK which supports the fingerprinting of children in schools through biometrics so they can use the library or buy food. The beauty of what the party has done is these young people don't have the images of 1940s Germany, or that fingerprinting is for people who break the law.

"The aim is to make them grow up thinking fingerprinting is absolutely fine and ID cards are a natural extension of that.

"People will be desensitised so they don't feel like criminals, although they are being treated like them."

Hosein said the scheme doesn't breach the data-protection laws because it takes only partial data, rather than the individual's full profile, and is destroyed within 24 hours.

He added: "Although it doesn't contravene the law, it breaks the law of humanity which is that you don't fingerprint innocent people."

Hosein said an iris recognition system, which has also been trialled at Heathrow, is more acceptable than fingerprinting.

He said: "I've signed up to it as I know if they are abusing my data, I can complain to the privacy commissioner."

Geraint Bevan, spokesman for No2ID Scotland, said the technology highlighted the vulnerability of people's privacy because it could be open to abuse by staff or passengers who could easily forge fingerprint details to avoid immigration checks.

He said: "At the least, it will cause complacency among check-in staff who may not pay as much attention to your boarding cards if they are busy checking fingerprints and photographs.

"There are also rogue workers in any industry who could take advantage of this information. Once you give information to anybody, you are at their mercy and must hope they act responsibly with it."

Accountant Elaine Richford, 26, was fingerprinted as she prepared to board a Glasgow-bound British Airways flight from Heathrow on Friday.

She said: "I was extremely taken aback as it had never happened before and there was no warning.

"It was quite scary.

"I am a little uncomfortable about what they are running my information against and what background checks are taking place on me." Richford, from Glasgow, was handed a leaflet which made it clear those who don't comply will be "invalidated entry" to their flight.

A BAA spokesman said: "We have been trialling the scheme for three or four months, but we have started to carry it out on a mandatory basis ahead of the opening of Terminal Five."

He said the data was destroyed at the end of each day and there was "no chance" it would be passed on to other authorities, including the police.