Up to 7,000 licensed security workers - including many pub doorstaff - will prove to be illegal immigrants following the current crackdown.
That is the prediction of the Security Industry Authority (SIA). It's not known what proportion of the 7,000 will be doorstaff but it could be in the thousands as 40% of SIA licences are for doorstaff.
In an exclusive interview with the MA, SIA chief executive Michael Wilson said around 10,200 licence holders suspected of being illegal immigrants have been written to.
The SIA will move to revoke licences if they can't prove their right to work here. "We had 2,600 responses back in the time limit saying, 'I have the right to work', and it looks like most of them will have - I can't say for certain.
"Of the 10,200 letters we sent out we've had no response - or far too late a response - from 7,000. We are anticipating that as well as the 16,000 [people currently on the register of revoked licences] we can add on another 7,000 or so."
Responding to allegations in BBC's Panorama show that criminals can run security firms by claiming to be "security consultants", Wilson said: "We don't think it's a widespread problem.
"We are not pretending it doesn't exist but it's not typical from the intelligence reports we get."
Wilson said there are "relatively few allegations of malpractice", adding: "We are satisfied that all allegations are investigated and the awarding bodies take appropriate action."