LONDON - Hundreds of bogus colleges set up in Britain are playing with future of Pakistani students as they have long been considered the biggest loophole in British immigration controls. Often little more than two rooms over a takeaway restaurant or newsagents, the colleges have been enrolling hundreds of overseas students each year to enable them to obtain visas. Phil Woolas, British Immigration Minister, described the bogus colleges last month as the Achilles heel in the immigration system. The govt announced a crackdown on them in 2003 but regulations did not come into force until the end of last month. Under the new rules, all universities, colleges and schools must be approved by the UK Border Agency before they can issue visa letters to foreign students. Of the 2,100 institutions that applied for a sponsor licence, 467 have failed the vetting. More than 3,000 other colleges estimated to have been accepting foreign students have not applied for a licence. For a few thousand pounds, students could enroll on a course that they never intended to take before beginning to work illegally and later applying for indefinite leave to remain in Britain on the basis of the amount of time that they have been in the country. Many of the colleges advertised courses in English and citizenship to help students to pass Home Office immigration tests or work-related courses such as door supervision and IT. The British Home Office has not published the names of the colleges that have failed the vetting or the identities of the institutions that failed to apply. The new rules make colleges responsible for their overseas students. They must keep a copy of students passports, report them if they fail to enroll, or drop out of a course, and raise any concerns if they are working or suspected of being involved in terrorism. At present there are 240,000 non-EU students in Britain. Government figures show that more than 43,120 Pakistani citizens were granted student visas between 2004 and 2007. Three years ago the British High Commission in Pakistan told the Commons Home Affairs Select Committee that it believed that about half the students to whom it granted visas disappeared after reaching Britain. The Pakistani High Commissioner in London criticised the govt last week for doing too little to run checks on foreign students. Wajid Shamsul Hasan said that Pakistan had not been allowed to carry out background checks for possible links to extremists on people applying to study in Britain. Asked if there was a problem with the British system for issuing visas, he said: The thing is they have their own regime - the regime that vets these people. But unfortunately in every system certain mistakes are made.