A CARE home for people with severe learning difficulties is under investigation by health watchdogs and the police.
All the residents have been removed from Veilstone Care Home in Buckland Brewer.
The move came after a whistleblower raised concerns about inappropriate use of a "quiet room" and CCTV cameras.
The Government-funded Quality Care Commission (CQC) was contacted by a source at the home near Bideford last month.
He is believed to have raised concerns about shutting residents in a "quiet room" for extended periods of time and watching them on CCTV cameras.
Nine residents, including some whose care was paid for by Devon County Council, were removed after an unannounced inspection by the CQC last month.
The CQC issued a formal warning to Atlas Project Team Limited, which runs the home.
Police are carrying out a criminal investigation.
A police spokesman said: "Police are currently investigating a number of allegations regarding levels of care received by residents at Veilstone.
"The investigation is ongoing and no arrests have been made."
A CQC spokesperson said: "Inspectors found that the provider, Atlas Project Team Limited, was failing to meet government standards covering the care and welfare of people, and respecting and involving people who use services.
"Inspectors were shown an unsuitable room which was being used for people to spend time in and sleep overnight.
"A surveillance camera was used to monitor people while they were in the room, but there were no risk assessments in place for each person on the use of the 'quiet room', or the use of the camera.
"Inspectors said the provider had failed to discuss a particular course of care or treatment with appropriate healthcare or social care professionals.
"They, and relatives or other representatives, were not properly involved in decisions relating to people's care and treatment, including the use of the 'quiet room'.
"On a second visit to the home inspectors were told that the 'quiet room' was no longer in use, but it was clear that the provider had not taken steps to ensure that people were properly protected against the risks of receiving inappropriate or unsafe care or treatment."
Ian Biggs, regional director of CQC in the South West region, said: "We needed to ensure that people living at Veilstone were not at any immediate risk of harm, which is why we have been working closely with the Devon Safeguarding Adults team to ensure the safety of all the residents.
"Following that intervention, all the residents have now moved out of Veilstone. The provider has assured us that they will stop all new admissions for the time being.
"The law says that these are the standards that everyone should be able to expect. Providers have a duty to ensure they are compliant.
"This warning sends a clear and public message that Atlas Project Team Limited needs to address this issue as a matter of urgency or face serious consequences.
"If at any time in the future Veilstone intends to open to new admissions, we will ensure that Atlas Project Team has made the required improvements. We won't hesitate to use our legal powers to protect the people who use this service."
The CQC told the Journal it will publish further details of the inspectors' findings in a review of compliance on its website at a later date.
Nobody from Atlas Project Team was available to comment.
A spokesman on behalf of Devon safeguarding adults' partnership said: "A safeguarding adults team, comprising representatives from Devon County Council, NHS Devon, Devon and Cornwall Police, Devon Partnership NHS Trust, and CQC are monitoring the home to assess whether it is providing appropriate care.
"A police investigation is underway, and as a precautionary measure alternative provision for the residents has been found, two of whom were placed by NHS Devon and Devon County Council, and six from other authorities.
"The safeguarding team is working with other local authorities and families of residents placed at the home to minimise any disruption or distress that such a move may cause. Because there is currently a police investigation into the matter it would be inappropriate to make any further comment until these investigations are completed."
Have you been affected by the investigation at Veilstone? Call the newsroom on 01271 347438.