Patients with a learning disability or autism housed in secure hospitals are vulnerable to a major abuse scandal if institutions are not properly managed, the Care Quality Commission has told Sky News.
Paul Lelliot, the mental health lead for the hospital inspectorate, said there was still the potential for patients to suffer abuse similar to that uncovered at the notorious Winterbourne View hospital in 2011.
Six members of staff were jailed for abusing vulnerable patients at the south Gloucestershire unit. Another five were given suspended sentences.
The people they were supposed to be looking after were, at various times slapped, soaked in water, trapped under chairs, taunted, sworn at and had their hair pulled and eyes poked.
The Winterbourne View scandal prompted an overhaul of government policy on the treatment of people with learning disabilities and autism.
It made a commitment to close up to half of the beds in hospitals known as Assessment and Treatment Units (ATUs) by March, a target that is going to be missed, and to move patients into appropriate community care.
A Sky News investigation this week revealed that more than 2,300 people remain inside ATUs, with many of them subject to years and sometimes decades of detention, and that at least 40 people have died while admitted to an ATU since 2015.
Mr Lelliot told us people with a learning disability and autism were at risk.
"They are particularly vulnerable people with a learning disability, often don't have the capacity to make a decision about their own care and I think they are vulnerable to exploitation and abuse," he said.
"I'm very aware of the potential for abusive practices to develop as they did at Winterbourne View, and I am very aware there is a danger of institutions developing that have the same characteristics as Winterbourne View did.
"It is vital that we don't let our guard down and we have to be constantly aware."
He also warned that hospitals in remote locations providing space to patients from different commissioning areas around the country were of particular concern.
"There is a danger of institutions being established in out of the way places. In some of these hospitals and residential care homes, there are many bodies purchasing places.
"If you have a number of local bodies it is rather unclear which commissioning authority has responsibility to oversee them."
Mr Lelliot's comments came after Health Secretary Matt Hancock told Sky News said he was "not happy" with progress on the bed closure programme, and said speeding up the movement of people from institutional care to their own homes was a priority.
"I've been following this since I became health secretary and I think it's absolutely heartbreaking," he said.
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"There was a target put in place a few years ago to reduce by a third the number of people in secure hospitals in this way and we're making progress against that target, but I would clearly want to see that go further and it's something we're actively working on.
"The numbers are coming down, which is good, but clearly there's more that needs to be done."