By Adam Brimelow BBC Health Reporter

They are worried the practice will spread as councils struggle to get to grips with the government's forthcoming community care legislation.

At Elmcroft - a residential home in Shoreham, West Sussex - there is a growing sense of anxiety running through residents, their families and care professionals.

I think you can go into any part of the country and possibly find where relatives and carers have been railroaded into paying towards care costs Paul Martindale Counsel and Care

With an ageing population, demand is growing all the time, but since April last year in West Sussex 37 residential homes and five nursing homes have gone out of business.

All this has increased the pressure for places at the remaining homes.

Sometimes families are being asked to top up the fees - and that is causing anxiety and resentment.

A woman who fought a long battle against West Sussex Council over top up charges - and asked not to be identified - told the BBC: "I was actually with the social worker and mum in her room when they told me I'd have to pay this money, and I practically collapsed.

"I couldn't think how we're going to find it."

Growing issue

Charities working in this field say it is a growing problem right across England.

They say many local authorities are refusing to make their full contribution to care home costs and they are getting families to make up the shortfall.

Paul Martindale from the charity Counsel and Care said he had dealt with dozens of complaints. He said: "I would say it's an epidemic.

"I think you can go into any part of the country and possibly find where relatives and carers have been railroaded into paying towards care costs.

"The finance departments are the people that are now, for me, running social services departments."

Local authorities insist they are acting within the law.

They say they are simply overstretched and the pressure on them is growing all the time.

From April next year the government plans to impose fines, or "reimbursement charges", on authorities that cannot provide care for patients once they are ready to be discharged.

The Local Government Association says that could lead to people being sent home too soon, or given the wrong kind of care.

More money

The government is putting in more money to help councils cope - an extra billion pounds for older peoples services by 2006.

Last month it announced a further �100m annually for social services to cushion the transition.

But the Local Government Association says it's not enough.

And charities are worried that as councils find themselves under even greater pressure, they will try to pass on still more of the costs to older people and their families.