Evidence of abusive treatment of disabled people has been captured by secret filming for BBC Panorama, in an echo of the Winterbourne View scandal eight years ago.

An undercover reporter employed as a care worker filmed colleagues taunting, provoking, intimidating and repeatedly restraining patients with learning disabilities or autism at the private Whorlton Hall hospital near Barnard Castle, County Durham.

The footage, to be broadcast on Wednesday night, has striking parallels with Panorama’s reporting in 2011 of ill-treatment of patients at the Winterbourne View unit near Bristol. Ministers pledged to run down such hospitals, known as assessment and treatment units (ATUs), and move up to 3,000 people placed in them.

Action has since faltered, however, and more than 2,000 people remain in the units, some run by the NHS but others operated by private companies paid up to £4,000 a week for each patient referred to them because community services cannot deal with the individual’s behaviour.

Sir Stephen Bubb, a charity sector leader who was asked to review progress on the government’s plans in 2014, said the latest revelations showed the promise of reform had been broken. “We will continue to have these scandals while we have these institutions,” he warned.

The Panorama reporter Olivia Davies worked shifts at Whorlton Hall over a two-month period at the beginning of the year. She filmed staff referring to the 17-bed hospital as a “house of mongs” and to patients as “fat cunt” and “a good fucking target”.

One female care worker is shown saying to a highly distressed woman: “If this is about your family, I’ve already told you they are fucking poison.” Glynis Murphy, a professor of clinical psychology and disability at Kent University’s Tizard Centre, comments in the programme: “I wouldn’t speak to a dog like that.”

In another segment, described by Murphy as “psychological torture”, male staff deliberately intimidate a young female patient who has a fear of men – and is supposed to be cared for by women – and use explicit sexual language and play on her phobia of balloons, seemingly to upset her further.

A third episode shows a male patient restrained on the floor by some of a group of seven staff present, one of whom has the man’s head trapped between his knees while laughing, wearing the man’s glasses and distributing chewing gum to the others. This staff member then tells another to strip the patient’s room of all his possessions, which she ostentatiously carries past him while he remains restrained and highly distressed.

Although there is no footage of assaults on patients, staff are shown discussing unauthorised restraint techniques and ways of inflicting pain without it being detected.

Davies said six care workers told her they had deliberately hurt patients. One is filmed saying: “If these guys say what we do to them, one day we will get into trouble.” He then recalls how a colleague dealt with a patient who “hit the deck like a sack of shit”.

A female care worker tells Davies she can be confident a female patient will not act up with her because she knows “I would fucking rugby tackle the cunt down”.

Whorlton Hall was formerly owned by Castlebeck, the company that ran Winterbourne View, which closed after the scandal. When Castlebeck failed in 2013, Whorlton Hall was bought by the Danshell Group. Danshell was in turn taken over last year by US-owned Cygnet Health Care.

Cygnet said in a statement that it had been “shocked and deeply saddened” by Panorama’s revelations. “Those implicated in this programme have betrayed not only some of society’s most vulnerable people, but also the thousands of people at Cygnet who work daily with dedication and compassion to look after the people in their care,” it said.

The company said it had suspended the 16 members of staff believed to have been involved, informed the police as soon as it was made aware and moved all 12 patients to other units. The hospital was “now closed”.

Durham police have launched a criminal investigation, which is thought to involve four agency workers as well as the 16 staff, and the Care Quality Commission regulator has said it is reviewing all Cygnet services and has carried out unannounced inspections of several sites.

Whorlton Hall was rated “good” by the CQC at its previous full inspection in 2017 and Cygnet says inspectors visited on seven occasions in 2018-19. Dr Paul Lelliott, the CQC’s mental health lead, said the commission had raised concerns about training and staffing but had not revoked the rating. “It is clear now that we missed what was really going on at Whorlton Hall, and we are sorry,” he said.

The scandal broke days after the CQC published a report on the use of restraint and seclusion in mental health services, and Matt Hancock, the health and social care secretary, announced a package of measures in response.

Ministers will now come under fresh pressure to address the ATU issue directly. A Department of Health and Social Care spokesperson said: “We treat any allegations of abuse with the utmost seriousness.”