The Home Office has suspended English language tests run by a major company after a TV investigation claimed that Britain’s student visa system is riddled with fraud.

BBC1’s Panorama programme said it had found blatant and routine cheating in Government-approved exams and a thriving market in false documents enabling people to stay in Britain illegally.

Researchers found that, for a fee, criminal immigration agents can help people get around language tests which are necessary for a visa to be obtained – even if they speak little or no English.

One immigration consultancy business in London offered a guaranteed pass for a £500 fee, before sending one of the programme’s undercover students to sit the English exam at a college designated as “trusted” by the Home Office.

Undercover footage shows the student making her way to a secure computer terminal linked up to a Government-approved testing company to take a test accepted by the Government for visa applications.

Footage showed a dozen-or-so other candidates in the room standing aside from their desks to allow ‘fake sitters’ to take the exam for them.

In the footage, the ‘fake sitter’ taking the BBC researcher’s exam is seen answering questions in the written and oral papers in perfect English. Meanwhile the registered candidates are seen standing quietly in the aisle waiting their turn to be called to the front of the room to have their photo taken by an invigilator to ‘prove’ they have sat the test.

The undercover researcher returned to the same test centre a few days later and filmed the second half of the exam, the multiple choice. In the footage, the invigilator is seen simply reading out the answers to all 200 questions so the registered candidates can copy them down. A two-hour test took just seven minutes to complete. A few days later, the researcher received a genuine exam certificate showing she had passed with high marks.

Panorama said tests are run by ETS, one of the biggest English language testing companies in the world.

Home Secretary Theresa May said: “The student visa regime we inherited was open to widespread abuse. It neither controlled immigration nor protected legitimate students from substandard sponsors. Our reforms have curbed abuse by closing bogus colleges, making the application process more rigorous and imposing more rules on colleges to improve course quality.

“However, as Panorama has highlighted, much more needs to be done. This type of abuse is not acceptable and as criminals, bogus colleges and economic migrants seek new ways to exploit the system we will continue to change our methods to clamp down on them.

“All further English language tests done through ETS in the UK have been suspended.”

Shadow home secretary Yvette Cooper said: “This investigation shows (Home Secretary) Theresa May is presiding over a failing immigration system which too often focuses on the wrong thing and where illegal immigration is a growing problem.