Despite raids by police and the high-profile conviction last year of Hull man David O'Donnell for masterminding a major counterfeiting operation to supply fake DVDs to traders, officials say there continues to be organised illegal activity at the Walton Street market.

Today several police officers will be on duty, together with around 10 staff from market operators Town and Country, as traders arrive at the site.

They will only be able to get onto the site through one entrance and will be asked what they are selling.

The move will hit people selling second-hand goods and blank DVDs but officials say they have to get the message across that the city will no longer tolerate the sale of counterfeit goods.

A council spokesman said they hoped to allow genuine traders whose goods meet Trading Standards requirements back onto the market within weeks.

He said: "The problem was persistent and was at a scale where literally we needed to do something about it. There is clearly an organised illegal activity taking place and that is something the council could not accept.

"We have spent the last eight weeks working with Town and Country and we have been advised by the police in terms of putting together an action plan.

"We have had to be fairly blunt in terms of saying we have to ban all audiovisual material because it is very hard to distinguish in some cases between the counterfeit and the original merchandise."

He added: "For those genuine traders who are selling genuine goods we want to vet those and have a facility so that they can be approved and allowed to trade on site."

Britain now has the world's second-largest black market in pirate films after the US, with about 49.5 million counterfeit DVDs sold last year, compared with 32.5 million in 2006.

The Walton Street market is held every Wednesday and Sunday from 7am onwards.