Recruiters are calling for tighter screening of immigrants from employers and the government's Security Industry Authority (SIA) after an investigation revealed 10,500 were either not licensed or had no right to work in the UK.

The SIA, which introduced licences for immigrant candidates wanting to work in the UK, was criticised for not checking whether employees had the right to work in this country after newspapers reported that 12 illegal workers had been employed to guard Metropolitan Police cars and one had overseen repairs to then Prime Minister Tony Blair's car.

Recruiters say the onus should be on both the recruiter/employer and the SIA to comprehensively screen candidates. Tom Craven, managing director of contract guarding agency Momentum Security, told Recruiter: "The gap in the armour is that the SIA did not have the legal responsibility to carry out checks on candidates' legal right to work in the UK.

"But companies have to satisfy themselves whether the guy is legal or illegal. There is a huge pressure to man sites and fill shift patterns all the time in the right locations. Would they turn a blind eye? I would hope not."

Craven said he uses "robust" pre-screening processes, including asking for and checking 'A-list' documents like passports and driving licences to avoid identity fraud and ensure that candidates are legally allowed to work in the UK.

Richard Plaistowe, MD of RIG Investigator and Security Careers, said: "There are rigorous British standards for working in the recruitment industry, such as requiring a minimum of five years' references from employers, credit reference checks and personal references. We make sure our candidates are fully vetted. But it is quite a transient workforce, with short-term positions. However, every employer should have been aware of the requirements for SIA licences and should have made sure that they employed people with the right to work in the UK.

"I think the SIA have missed a trick. When they set up organising licences they didn't make sure people were eligible to work in the UK."

Andy Drane, director of operations at the SIA, told Recruiter that services had been improved and tighter controls have been built into the application procedures.

"We are refusing and revoking more licences than ever before (9,700 refused and about 700 revoked).

"Employers still need to make sure they carry out responsible checks on their licensable employees."