Two illegal immigrants from India earned millions of pounds from a visa fraud “factory” that helped an estimated 4,000 bogus students to cheat Britain’s “shambolic” border controls.

The married couple, Jatinder Kumar Sharma and Rakhi Shahi, aided by a network of sham colleges, sold fake academic certificates to clients, who paid up to £4,000 each for a false educational history that would gain them the right to live in Britain. Their success, a Crown Court jury heard, was a damning indictment of the Home Office.

Those involved were so confident of fooling immigration officials that they offered a money-back guarantee to any customer denied a visa.

Police and UK Border Agency (UKBA) officials found 90,000 documents during a raid on two warehouses and the premises of a company called Univisas, in Southall, West London, in February last year. The operation led to the agency’s biggest investigation into organised immigration fraud and the discovery of an international criminal network stretching to the Indian sub-continent.

At least 1,000 illegal immigrants are known to have used Univisas to enter or stay in Britain but The Times has been told that the true figure is likely to be more than 4,000.

Sharma, 44, a solicitor, and Shahi, 31, are believed to have earned at least £3 million from their role in the fraud. Individuals running one of the London colleges that provided them with sham certificates and diplomas are thought to have been paid £9 million for their work.

Employees at the London School of E-Commerce supplied fraudulent material including degrees, diplomas and employment material to the criminals. It ran only one questionably accredited nursing course but had a huge number of clients on its books.

At Isleworth Crown Court yesterday Shahi was convicted of conspiracy to defraud, handling criminal property and immigration offences. She was sentenced to eight years in prison. Sharma pleaded guilty to his role in the conspiracy before the trial started and was sentenced to seven years.

A third woman, Neelam Sharma, 38, was convicted of handling some of the money and was jailed for four years. The former teacher was cleared of conspiracy to defraud and immigration offences.

When the police raided their offices they found evidence that Jatinder Sharma planned to move the business to India, where he could operate out of reach of the British authorities.

The case comes less than two weeks after The Times revealed how thousands of Pakistanis used 11 sham colleges in Manchester, Bradford and London to exploit Britain’s immigration defences.

During the month-long Univisas trial Francis Sheridan, for the prosecution, said: “The Home Office system was designed to operate with trust. The evidence shows it was naive in its conception and a total shambles.”

The court heard that in a secret recording one member of the gang boasted that Home Office officials “don’t even bother to look” at visa application documents to check their authenticity. They “just stamp them blindly”.

Mr Sheridan said: “It is believed this prosecution represents the largest single prosecution of dishonest records ever submitted to the Home Office by an individual business. It is a huge attack on the system.”

The gang, he said, “were acting on behalf of clients . . . to cheat the Home Office wholesale” and had “made a small fortune” as a result. A former Univisas employee described how £64,000 in £50 notes changed hands at one college in return for a pile of certificates.

Among the documents seized were false university certificates from India and Pakistan, false academic records from British colleges and fake bank statements and pay slips. Many of the impeccable but totally false academic records were used by the clients to obtain two-year post-study work visas.

Passing sentence, Judge Richard McGregor-Johnson said: “Various criticisms have been made of the actions of the agencies responsible for checking those documents. Those criticisms are plainly well founded in my view. The checks were woefully inadequate and frequently non-existent.”

He recommended that the defendants be deported at the end of their sentences.

The visa-fraud empire collapsed after an undercover local newspaper journalist found evidence of the counterfeiting operation. The jury was shown the company’s prices for services, ranging from false degree certificates to leave-to-remain visas.

The figures were contained in e-mails exchanged between Shahi and a member of staff at the Indian-owned London School of E-Commerce, which has operated from five addresses in Essex and London since 2000.

Detective Chief Inspector Robert Hoey, of UKBA, told The Times: “We know of 1,000 foreign nationals who have come illegally into this country, but what we have discovered so far is merely a snapshot. It was an extremely sophisticated scheme.”

Tony Smith, the regional director of UKBA, said: “Organised immigration crime is a serious problem. This is the biggest investigation we have undertaken and it’s a major breakthrough into organised immigration gangs.”

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