THE Government's failure to tackle the problem of bogus colleges has allowed tens of thousands of illegal immigrants to come to the UK, a damning report said today.

THE Government's failure to tackle the problem of bogus colleges has allowed tens of thousands of illegal immigrants to come to the UK, a damning report said today.

The House of Commons Home Affairs Committee said most came in on fraudulent visas in order to work illegally and not to further their education.

Committee chairman and Labour MP Keith Vaz said it was "unacceptable and unbelievable" that ministers had done nothing about the problem despite knowing about it for more than a decade.

He called for "immediate action" to stem the flow of bogus students, and said the committee was "not convinced" effective action was being taken to ensure students whose visas have expired are being made to leave.

He said: "Bogus colleges may have allowed tens of thousands of foreign nationals to enter the country illegally: the Government has been aware of their existence for ten years and done nothing to stop them," he said.

"This is totally unacceptable and frankly, quite unbelievable.

"This should not be allowed to continue and action must be taken immediately.

"Firm enforcement action must be taken against any individual whose student visa has expired to ensure that they leave the country, as well as against those who have set up bogus colleges to perpetrate visa fraud.

"We are not convinced that this is happening at the moment."

The report questioned the rigour of college inspections by officials and criticised the UK Border Agency for giving advance notice of inspections to more than 80% of colleges.

Use of the term "college" should be restricted to registered institutions, the committee said.

Earlier this year, Immigration minister Phil Woolas admitted bogus colleges were the "Achilles heel" of the immigration system.

Fears were raised over the checks carried out on foreign students after a group of Pakistani students was arrested in anti-terror raids in the North West of England.

No charges were brought, but the Home Office is still trying to deport seven students on the grounds they pose a threat to national security. Two others face deportation over visa irregularities.

Mr Vaz said the committee found "no substantial evidence" of a link between bogus colleges and terrorist activity.

Since March this year, all education institutions which want to bring non-EU students into the country need to be approved by the UK Border Agency.

But the report revealed Home Office concerns over the effectiveness of checks on colleges from two years ago.

A UKBA report in 2007 found: "an unknown number of private institutions are operating largely to provide low quality teaching to those wishing to enter or remain in the UK as students whilst working illegally".

It revealed officials were checking bogus colleges already on a Government list of approved institutions, instead of examining them when they applied.