Illegal immigrant was working at front desk of Home Office

The Home Secretary Jacqui Smith faced huge embarrassment last night after it emerged that an illegal immigrant had been caught working on the front desk at the Home Office.

The Nigerian man was picked up as immigration officers examined the status of more than 11,000 foreigners mistakenly cleared to work across Britain.

Aides said the Home Secretary was furious over the discovery of an illegal worker within her own department. The security guard had been in the department for about 18 months, checking the passes of visitors to the Home Office.

The man, supplied to the department by a sub-contractor, faces deportation after being arrested on Friday night.

The Border and Immigration Agency had been examining the records of 11,100 non-European Union nationals given permission to work by the Security Industry Authority (SIA).

It uncovered problems with a sub-contractor and the trail led it to the Home Office, its own department headquarters.

One security guard was detained and the immigration status of all others supplied by the sub-contractor to Ms Smith's department are being checked.

The Home Secretary added in a written statement to MPs last night: "The Permanent Secretary has taken immediate steps to tighten the procedures for checking the immigration status of those working in the Home Office, whether as a civil servant, employed by a contractor, or in any other capacity."

The latest episode echoes the discovery last year of five illegal immigrants working as cleaners in immigration offices just days after John Reid became the Home Secretary.

David Davis, the shadow Home Secretary, said Ms Smith had been at pains last week to blame employers for the "SIA shambles".

He said: "If she is going to try and avoid responsibility in such away she should at least check her own house is in order.

"Who will the Home Office now prosecute and fine? Itself?" He added: "It is clear this Government is part of the problem, not the solution." Jeremy Browne, the Liberal Democrat home affairs spokesman, said: "The Home Office seems to mess up with depressing regularity, but this latest breach of security goes literally to the heart of government."

The blunder over security guards emerged in the summer after an illegal immigrant was found guarding the yard where the Prime Minister's car was taken for repairs.

It was also disclosed that Ms Smith had accepted Home Office press office advice in August not to tell the public about immigration control mistakes.

When the problem became public, initial estimates put the figure of numbers affected at 5,000.

But last week Ms Smith indicated the figure could be as high as 11,100.

She disclosed that the SIA handed permits to 6,650 illegal workers, plus a further 4,450 people who officials believe may not have the right to work.