Laws are now in force requiring all door staff to be licensed by the Security Industry Association (SIA).

In checks of more than 200 bouncers at the weekend South Yorkshire Police found 42 without the qualification.

Up until last month, only half of the city's 350 bouncers had received their SIA licences.

There was a lot of late applications which have clogged up the system Scott Bailey, club owner

The weekend operation was the first time officers had enforced the new legislation since it came into effect in December.

Insp Sean Morley, who led the operation, said: "We've heavily publicised the fact we were going to enforce the legislation and all the door staff in Sheffield city centre are fully aware of the requirements to register.

"A high proportion simply had not applied because of their previous criminal history and those are the people we are trying to weed out and remove from the doors of Sheffield."

Scott Bailey, who owns the Dot Zero nightclub in Sheffield, believes that some of the licenses are likely to have been held up by red tape

Mr Bailey - also deputy chairman of the Sheffield pub watch scheme - said: "I think that some of our members have cited a few problems related to the administration process.

"There was a lot of late applications which have clogged up the system.

"I think most people who applied in time have got their SIA badges back."

Under the new rules, the security company that employs unlicensed bouncers and the licensee of any premises allowing them to work could both be prosecuted.