A health trust has been placed in special measures after inspectors found some mental health patients were at risk of harm.
The Isle of Wight NHS Trust has been rated "inadequate" by the Care Quality Commission (CQC).
Its report found "unsafe" mental health services, widespread understaffing and a "subtle culture of bullying".
The trust's chair Eve Richardson said they accepted the report "without reservation".
The CQC said the island's "inadequate" ambulance service, mental health provision and the trust leadership were most at fault.
Community health and acute hospital services were rated as "requiring improvement".
Analysis: David Fenton, BBC South health correspondent
I have seen many reports from the CQC and this is one of the worst - if not the worst.
Failures at almost every levels in the trust have been laid bare.
Perhaps most worrying is the suggestion that patients were put at actual risk of harm.
People use the NHS to get better, not to be made worse.
Despite the criticisms, staff were said to be "caring" - which many patients told me is true.
Inspectors, who visited the trust in November, found community mental health services had been wrongly restricted to patients with the "most complex and urgent needs".
On hospital wards, mental health patients had "access to electrical cupboards, live broken electrical sockets, continually failing personal alarm systems and ligature points".
The CQC imposed an urgent improvement notice because of the risk of patient harm.
At St Mary's Hospital in Newport, the watchdog found the emergency department "did not meet minimum registered nursing levels for safe care".
One patient with a serious heart and lung problem described how he was left on a trolley in a corridor for 13 hours.
Stuart Clements said he had to throw pieces of newspaper over the cubicle curtain to attract doctors' attention because his emergency buzzer was hidden from view.
Staff at the trust-run ambulance service were also found to be working with an "unreliable" mobile data system which "sometimes froze", leaving them with no navigation system or patient details.
Further, an ambulance station was deemed "not secure", with the trust taking more than a year to replace a garage door.
Karen Baker stood down as the trust's chief executive in March, ahead of the CQC's report.
The trust apologised for "letting down patients and the community".
Ms Richardson said: "Our sole focus now is to absorb the lessons contained within this report, to develop, with our partners, an effective and comprehensive improvement programme and to ensure it is implemented as swiftly as possible."
The trust said it had already begun making improvements including the reduction of agency staff, the recruitment of a director of human resources and changed arrangements to prevent multiple bed moves for patients.
It said £600,000 had been set aside for improvements to buildings used by mental health services.
NHS Improvement said it had appointed a director to work with the trust as part of a package of support measures.
Healthwatch Isle of Wight said it was disappointed to see a number of issues raised in the latest report also featured in a 2014 inspection.
The independent campaign group added: "Despite their previous assurance that they had action plans in place to address all the issues identified in the 2014 CQC inspection report, it would seem that to date, these initiatives have not proved to contribute to a long-term solution.
"We are aware that the trust is already taking action to address many of the issues identified by the CQC during their [latest] inspection... but the real test will be how these actions translate into rapid and sustained improvement of patient services.
"Isle of Wight residents deserve a healthcare service that meets their needs, delivers the right care in the right place at the right time. This is not too much to ask and is nothing less than people deserve."