More than 6,000 illegal immigrants were cleared to work in the security industry, the home secretary has revealed.

A quarter of non-European Economic Area nationals registered with the Security Industry Authority (SIA) should not have been given professional licences, MPs were told on Thursday.

Jacqui Smith told the Commons that of the 39,885 non-EEA nationals processed by the SIA before July 2 this year, 6,653 did not have a right to work in the UK.

In another 4,447 cases, the Border and Immigration Agency (BIA) does not believe the individuals have provide the right to work, she added.

Smith was informing MPs about the progress so far in dealing with the "significant problem" revealed last month with the system of licensing security guards.
 
The home secretary told MPs that, since July 2, the SIA had introduced immigration status checks on all non-EEA applicants and was seeking advice from the BIA on issues such as identifying forged documents.

Applicants processed before July 2 were being checked by the BIA, she said, and the SIA had issued more than 10,000 letters giving them 21 days to respond. So far, 409 licences have been revoked, with more expected in coming weeks.

The BIA had started investigations into 328 individuals, carried out 101 enforcement visits, arrested 15 people and planned another 400 visits by the end of January, Smith said.

Individuals were also being checked against the police national computer to ensure that those that pose a risk could be targeted.

Shadow home secretary David Davis demanded to know how the system had "gone so badly wrong" and described the situation as a "huge policy failure" in the Home Office.

He and other MPs asked whether the prime minister had been made aware of the problems in September and October, when he had been considering calling an election.

Smith said she had kept Gordon Brown "up to date" but had not told him before November 10.

Liberal Democrat leadership contender Nick Clegg said he had been following the "series of scandals that have disfigured this government's spectacular mismanagement of the immigration system" and had thought "we had seen it all".

But "this latest belated revelation of keystone cops incompetence truly takes the breath away", he added.