The operator of a residential hospital has apologised unreservedly and suspended a number of staff following allegations that carers routinely abused vulnerable adults with learning difficulties.

Police have also launched a probe and arrested four people after undercover footage of the apparent misconduct at Winterbourne View, in Bristol, was recorded by investigators from BBC’s Panorama programme.

The hospital’s operator Castlebeck said it was “distressed” and “shocked” by the accusations that workers physically and verbally abused residents on a daily basis.

The secret recordings, filmed between February and March this year, appear to show carers punching and slapping vulnerable adults, dousing them in cold water, and pinning them to the ground with chairs.

Thirteen members of staff including two managers have been suspended and three men and one woman had been arrested by Avon and Somerset police, according to the BBC.

All patients have been moved to safety.

Clinical psychologist Andrew McDonnell said he was shocked by the footage and labelled some of the examples captured on film as “torture”.

He told the programme that basic techniques for dealing with patients with challenging behaviour were ignored.

Company officials said they had not seen the footage ahead of last night’s programme, but were made aware about its contents on May 12.

“Castlebeck immediately notified the police, Care Quality Commission, the local Safeguarding team, commissioners of the service, other relevant authorities, and the families of the patients named in the allegations,” said a statement released by the firm.

“Staff alleged to have behaved inappropriately were suspended and reported to the police, who are now investigating.”

The company confirmed a former nurse had made a complaint about the quality of care to hospital managers in October last year.

However, it said its whistle-blowing policy was not followed correctly and due to “delays” in the process neither the chief executive or board members were made aware of it.

The former employee also contacted the CQC, which regulates the social care industry, but the complaint was not taken up.

Lee Reed, Castlebeck’s chief executive officer, said: “I was shocked, disgusted and ashamed by what I saw on Panorama.

“Having spent my entire career in health and social care, I intend to leave no stone unturned to ensure that this type of horrific event is never allowed to happen again.”

The company said it is now in “active consultation” with the appropriate authorities with regard to the future of privately-run Winterbourne View, which cares for up to 24 patients, employs around 50 members of staff and is funded by taxpayers.

It is also reviewing the records of all of their 580 patients and launched an internal investigation into its whistle-blower procedures.

An independent review of the company, that will focus in its culture, medical protocols and communications systems, has also been commissioned by directors.