Four workers at an Indian restaurant in March were detained tonight after a swoop by Home Office immigration enforcement officers.

A team of around six or seven officers walked into the restaurant shortly after 6pm and, three hours later, took all four men into custody.

Customers turning up to the Spice Bank in High Street, March, either voluntarily left or were asked to leave as the Home Office team used the dining room to question the suspected illegal workers.

The investigation would have focused on whether the Spice Bank – which changed hands earlier this year - was using illegal labour.

Immigration enforcement has previously described the use of such workers as “not a victimless crime. It cheats the taxpayer, undercuts businesses who ply an honest trade and deprives legitimate job seekers of employment opportunities.”

Throughout the three hour visit enforcement officials would have checked passports and working credentials of all those employed by the Spice Bank.

By 9pm the team clearly had sufficient detail to believe all four men detained were working here illegally and took them into custody.

The restaurant owners will have been issued with documents warning of a potential £20,000 fine for each illegal worker found.

However the restaurant will also have been invited to demonstrate the correct right to work checks were carried out, such as sight of a passport or Home Office document confirming permission to work. A Home Office spokesman said the four men, two 41-year-olds, a 27-year-old and a 26-year-old, were all Bangladeshi nationals.

They had all over stayed their visas and have been detained pending their removal from the UK.

He said inquiries were on-going over potential civil liability of the business owners, whether they were aware of the situation regarding the four men, and whether they had carried out the required checks under employment law.

The 65-seater Spice Bank opened in September 2013 in the former Lloyds TSB premises next to St Peter’s Church.

No one was available at the restaurant to comment on the arrests.