The Home Office admitted it "does not really know" the scale of the problem, John Vine, chief inspector of UK borders and immigration at the time, suggested the issue was "more widespread" than the figures suggested.
Sham marriages are when an individual gets married solely to gain British or European citizenship. Illegal immigrants often resort to sham marriages to settle in Europe. They are classed as immigration fraud in the UK
In 2016, a freedom of information (FOI) request revealed UK based sham marriages increased by almost 850 percent. The number of arrests rose from 137 in 2010 to 1,545 in 2014, while the number of incidents where Home Office officials suspected something untoward was happening rose from 204 to 2,488, according to London newspaper The Daily Express which requested the information.
Keith Vaz, who was chair of the home affairs select committee at the time, said: "The evidence is clear, criminal gangs are arranging sham marriages for huge profit all over the country."
In 2017, an investigation revealed thousands of people were using the so-called 'Surinder Singh route' to circumnavigate UK immigration rules after the British government introduced a minimum income for UK citizens before they could bring a wife or husband from outside the European Union into the UK.
Surinder Singh scammers create fake lives for people so it makes them look like they have genuinely moved to a European country, namely Ireland, when the reality is more likely that they have remained in the UK. Bank accounts, payslips and fake companies can all be set up to make cases more convincing. The report broadcast on BBC Radio 4 revealed 20,000 non-European family members arrived in Britain in this way.
Immigration minister Robert Goodwill said: "There is a growing industry, fed by unscrupulous immigration agents, that seeks to exploit free movement rules to help non-EEA nationals circumvent our immigration system, creating backdoor routes in the UK."
Meanwhile, a married couple in Britain are accused of arranging at least 13 fake weddings between Asian men and Lithuanian women who have the right to remain in the UK.
The Old Bailey heard Ayaz Khan, 32, and Jurgita Pavlovskyte, 25, allegedly earned US$698,000 from sham marriages, unproven allegations the pair deny.
The couple, along with Imran Farooq, 35, Diana Stankevic, 26, and Muhammad Saqlain, 32 claim all 13 marriages were genuine and all deny conspiracy to assist unlawful immigration. Khan and Pavlovskyte also deny acquiring criminal property and converting criminal property relating to payments made for the organization of marriages of convenience.
The alleged fake grooms all deny one charge of securing or seeking to secure the avoidance of enforcement action by acting as grooms. The alleged fake brides all deny one charge of assisting unlawful immigration by entering into marriages of convenience. The trial at the Old Bailey in London continues.