Police in Bristol have arrested four people after secret filming by BBC Panorama found a pattern of serious abuse at a residential hospital.
Following the airing of footage at Winterbourne View, which treats people with learning disabilities and autism, a number of organisations shared their thoughts.
CASTLEBECK GROUP CHIEF EXECUTIVE
Chief executive Lee Reed said he was "ashamed" by what had happened.
"All I can do is unreservedly apologise to both the families and the vulnerable adults that have been involved in this and recommit to making sure this doesn't happen again," he said.
CARE QUALITY COMMISSION
The Care Quality Commission, the government regulator, said that following an internal review it recognised that "there were indications of problems at this hospital which should have led to us taking action sooner".
"We apologise to those who have been let down by our failure to act more swiftly to address the appalling treatment that people at this hospital were subjected to."
SOUTH GLOUCESTERSHIRE COUNCIL
South Gloucestershire Council said it "takes all allegations of abuse and mistreatment of vulnerable adults very seriously".
In a statement, it said: "Our immediate concern is always for the safety and welfare of patients.
"As soon as the SAB [Safeguarding Adults Board] were made aware of these allegations at Winterbourne View... appropriate action was taken in line with established procedures and protocols."
CHRISTINA MCANEA, UNISON HEAD OF HEALTH
Christina McAnea, Unison head of health, said: "The abuse revealed in the Panorama programme is sickening. We need action and we need it now.
"These patients have been betrayed by their carers, by the hospital owners, Castlebeck, and by the Care Quality Commission, who all failed to take action, despite repeated warnings about abuse.
"Unison has long called for staff working with vulnerable adults to be given quality training - it is very revealing that, without any previous experience, the reporter got a job at Winterbourne View and was given just one week's training."
NATIONAL AUTISTIC SOCIETY
Carol Povey, of the National Autistic Society, called the abuse shown in the programme "disgusting" and said that current regulations are inadequate.
She said: "There have to be a number of checks and balances right across organisations. The external regulator, the CQC, has got to be robust and do unannounced inspections."
Chief executive of the learning disability charity Mencap, Mark Goldring, says CQC should be carrying out unannounced spot-checks to protect patients.
Mr Goldring said: "If you look at the quality of work that came out of the Care Quality Commission on a recent report on old people in hospital, where they had made those unannounced and hidden visits, what they uncovered was really important and was very much in the public interest.
"That needs to happen. CQC have got an approach which is about profiling risk, and in this case they had reason to act on that risk, because they'd had three whistleblowing reports. They'd also had a member of staff who'd been convicted of violence within the home in the last few months."
SHADOW HEALTH MINISTER EMILY THORNBERRY
Shadow health and social care minister Emily Thornberry says she is very concerned that the abuse was not stopped when a whistleblower revealed it to the CQC.
She said: "The fact that there had been complaints taken out by one of the senior nurses at that institution, who had got in touch with CQC, and CQC had failed to respond adequately, is something of huge concern.
"In the end this was criminal activity against the most vulnerable and we need to make sure that those people are punished. It is the most appalling abuse that was happening."
ROYAL COLLEGE OF NURSING
Dr Peter Carter, head of the Royal College of Nursing, said: "The sickening abuse revealed in this programme is more shocking than anything we could have imagined."
The Royal College of Nursing said there had been "failure" on the part of the CQC, and that the government should examine the training and regulation of health care assistants, as "it cannot be right that there are no national standards for those caring for vulnerable patients".
MP JACK LOPRESTI
Jack Lopresti, the MP for Filton and Bradley Stoke constituency where the hospital is sited, said: "The footage shown on last night's Panorama was shocking and haunting. To me the actions of some of the members of staff at Winterbourne View Hospital amounted to torture and assault against some of the most vulnerable members of our society.
"I have now written to the local PCT, the Quality Care Commission and Castlebeck Care concerning the future of the facility and for the outcomes of internal enquiries.
"Serious failures were clearly made by those responsible for the patients' well-being and care and these should be rectified and strong action taken as soon as possible."