A halfway house created for former rough sleepers turned into a "crack house", visited by dozens of addicts a day, its residents claim.

Amber House opened less than two years ago, promising supportive homes for people coming off the streets. But tenants now claim it provided a haven for drug dealers.

Labour MP David Lepper is demanding action to combat the problem at the block of 12 one-bedroom flats in New England Road, Brighton.

Mr Lepper, MP for Brighton Pavilion, said he had raised the issue with police after prolonged complaints from tenants.

He said: "The drug dealers moved in and targeted some of the flats. I first wrote to the police in November and I am concerned at their lack of response.

"I have been in touch with Sanctuary Housing Association, who had to employ security guards to look after the building.

"The police seem to have a policy of not cracking down on the small dealers while waiting for the big ones.

"Sanctuary suggests there are still serious lapses in co-operation between the police, itself and the security company it has employed.

"I hope to impress on the Chief Constable that it is necessary to take action to avoid undermining important aspects of the supported housing service throughout Brighton and Hove."

Mr Lepper said he knew of at least one other halfway house in Brighton with similar problems.

A police spokeswoman said: "If we are aware people are dealing, we will act but we can't shout from the rooftops what we have done.

"We have worked with Sanctuary right from the start and there are plans to improve the situation. We are always aware of the problems when a place like this is set up. "

Tenants, some of whom took their concerns to The Big Issue, the weekly magazine raising funds for homeless people, said the police presence had been almost nil.

One of them asked: "How did this lovely building end up as a crack house in less than two years?"

Ken Bunker, South-East director of Sanctuary Housing Association, said: "There isn't a problem at Amber House any more. The security guards have moved the problem out."

But he said the association was being extremely vigilant in ensuring the problem did not return.