DRUNKEN violence will soar in town and city centres when pubs are allowed to open round-the-clock, a Durham professor warned MPs.

Dick Hobbs, a professor in the university's law department, told the Commons home affairs committee that the Government's plans put the public at risk.

And he demanded that local authorities be required to prove they were providing extra police and medical staff before they could expand their "night time economy".

Without proper preparation, it would be impossible for the police, ambulance service and accident and emergency departments to plan their resources, he said.

Prof Hobbs was giving evidence to the committee's inquiry into the affect on anti-social behaviour of controversial plans to relax England's rigid licensing laws.

From next summer, pubs will be allowed to stay open after the traditional 11pm closing time if they have been granted a licence by their local council.

Ministers believe staggering closing times will curb trouble in city centres because drinkers will not leave pubs at the same time.

But they have already delayed the switch until after next May's expected General Election because of nervousness that the Licensing Act will backfire.

Prof Hobbs won government funding to carry out a study into "violence in the night time economy", which found a direct link between extra pubs and worse disorder.

In his written evidence to the committee, he demanded councils create a plan that ensures adequate police, transport, toilet, hospital and ambulance facilities.

The professor told the committee the average big city had a maximum of 20 officers to cope with 40,000 drinkers, which meant special constables had to be drafted in.

Asked about round-the-clock drinking, he said: "I see no justification for it.

"People are being put at risk and city centres are being put at risk."