Around 10,500 members of the Public and Commercial Services (PCS) union took the action in protest at the imposition of a below-inflation three-year wage deal.

The union said the average increase will be 1.9% a year, while the lowest-paid workers will receive increases of £7 a week.

The workers, based across the Home Office, including the Border and Immigration Agency, could take strike action if the row is not resolved, said the union.

PCS official Paul O'Connor said: "Morale in the department is at an all-time low and the imposition of this offer will do nothing to boost it.

"Management and Ministers need to enter into meaningful negotiations to settle this dispute or face the possibility of strike action."

General secretary Mark Serwotka said: "The imposition of this below-inflation three-year pay offer, along with that in the Department of Work and Pensions, illustrates that the government are intent on driving down the pay and living standards of dedicated civil and public servants.

"The government have got to recognise that their approach to public sector pay is breeding resentment and anger.

"Civil and public servants deserve a fair wage that doesn't result in their pay being cut in real terms."