Staffordshire mental health unit Eldertree Lodge in special measures
A police investigation is under way at a mental health unit that has been placed in special measures.
The Care Quality Commission (CQC) inspectors found "widespread and significant shortfalls" at Eldertree Lodge, in Staffordshire.
Its report said were not fit-for-purpose, there was not enough staff, and masks were work incorrectly.
Owner Coveberry Ltd said further work was needed but progress was being made.
In April BBC News reported the hospital, near Loggerheads, had its inspection rating suspended over concerns about the quality of care around the use of restraint.
An inspection was carried out in March and in its report, published on Thursday, the CQC said it found "inappropriate patient handling techniques, poor staff behaviour, unsafe staffing levels and a lack of visible leadership".
Patients were at risk of harm "because systems to monitor the quality of care were either not in place, or not operating effectively", it added.
'Programme of investment'
Some of the concerns were raised by Coveberry Ltd after it took over the running of the hospital, a secure unit for 41 patients.
Despite submitting an action plan within 24 hours of the inspection, Coveberry Ltd was restricted from admitting any new patients without agreement from the CQC and has also been rated as inadequate.
Dr Kevin Cleary, CQC deputy chief inspector of hospitals and mental health lead, said wards were not safe and clean, bathrooms had visible mould and hazardous materials were left in unlocked areas.
Analysis by Michele Paduano, BBC Midlands Today health correspondent
Eldertree Lodge - formerly known as Ashley House only came under new management in December.
Some of the problems are historical - particularly around the physical environment. But, 70% of trained staff are agency.
The report says that they do not know the needs of patients. They were not following the organisation's own restraint procedures.
Given the difficulties that appear to occur time and time again in these homes that look after the most vulnerable in our society - is the current model properly resourced and fit for purpose?
Staffordshire Police has confirmed it has started an investigation, but has not released any further details.
Agency staff could not describe the needs of the patients in their care and staff did not follow the Covid-19 infection control policy or national guidance.
In a statement, Coveberry Ltd said it recognised the need for improvements and had started an action plan which was hampered by Covid-19, although new leadership was now in place.
"We acknowledge that further work is needed but we are confident that progress is being made under the continuing programme of work and investment," it said.
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