Staff at the hospital, off Preston New Road, called in police, with one worker claiming the seriously ill man kicked his way out of a room that should have been triple-locked.
Officers found him in a field behind the unit and took him back, police said, with the incident leading to further concerns about staffing at the flagship facility.
Lancashire Care, the under-fire NHS trust responsible for mental health care across the county, said it was “unable to discuss details relating to an individual’s care due to confidentiality reasons”, but said: “We can confirm the safety of our patients, staff, and visitors is our number one priority at all times, and we have robust procedures in place to manage our safety.
“Ensuring the safe staffing of all elements of our services is a priority.”
After a medic spoke to The Gazette, the trust said it was “also planning to directly talk with staff about their concerns and see how we can best support them”.
The worker said the patient was taken to the 136 suite, for people who have been sectioned under the Mental Health Act, in the early hours of Wednesday, October 24.
He was put into a secure room, likened to a police cell, but at around 8.30am he “managed to kick open the secure door as staff had not triple locked it”, the staff member said.
They said the patient then escaped from the suite, “walked behind the hospital and made his way to the main entrance, where he proceeded to gain access to the kitchen area, frightening staff, and smashing windows.
“He then managed to get out again and make his way over the window opposite the hospital, but ran off towards Marton Mere Caravan Park, where he was apprehended by police.”
While accepting the man was “severely suffering” from a mental illness, the worker said: “This is another event where management continue to run the hospital at the bare minimum staffing, burning staff out, which leads to incidents like these where staff or the general public may have been severely injured.”
Lancashire Police said officers were called at 8.40am “by staff at The Harbour on Windmill Rise, Blackpool, requesting police assistance with a violent patient”, and said: “When police officers arrived, the man had escaped but was found in a field behind The Harbour.
“He was returned to the hospital.”
Lancashire Care added: “Ensuring the safe staffing of all elements of our services is a priority. We continue to use the safe care staffing system at The Harbour, which ensures our staffing levels are safe to meet patient need and provide quality of care.
“At times, we are required to allocate our workforce flexibly and according to service demand.”
An anonymous letter voicing “concerns about The Harbour” was sent to several bosses at Lancashire Care recently.
The same note was received by the chairman David Eva, chief executive Professor Heather Tierney-Moore, and medical director Professor Max Marshall.
The exact content of the letter was not divulged in a report seen by The Gazette, but it related to concerns about changes to staffing, specifically staff rotation and the timing of it.
As a result, the trust’s director of nursing and quality, Paul Lumsdon, “visited wards ... and communication was sent to staff including details of a follow-up visit,” the report said.
And a spokeswoman said: “The concerns raised by staff related to an operational change and the way it had been implemented.”
Last month, resort councillors said a lack of staff, beds, and cash have left mental health services in Lancashire “in chaos.”
Members of Blackpool Council’s health scrutiny committee criticised an improvement plan drawn up by Lancashire Care on the back of a damning inspection report by the Care Quality Commission (CQC).
The report, published in May, gave the trust a “requires improvement” rating and found nine breaches of legal requirements.
It comes during a troubling time for the Â£40 million unit, which has been dogged by problems and controversy since opening in March 2015, starting just months later when staff shortages forced the closure of a key ward.
In July 2016, an inquest ruled failings at the flagship facility contributed to the death of 20-year-old Sally Hickling, who died from brain damage after being discovered with ligatures around her neck.
Last November, it was reported how a patient being transferred from The Harbour, 39-year-old Tracey Lynch, was sectioned after causing a serious crash on the M55 motorway, but was released without being assessed and went on to kill herself.
And last month, The Gazette revealed how Blackpool coroner Alan Wilson wrote to bosses at Lancashire Care with concerns about record keeping following the suicide of Adam Carter.
The 36-year-old, from Thornton Gate in Cleveleys, fell from the fifth floor of the Talbot Road multi-storey car park last September, after running off during an escorted trip from The Harbour.
The damning report by the health watchdog CQC concluded Lancashire’s mental health services were ‘not safe, not effective, and not well-led’ in May.
Most recently, Blackpool South MP Gordon Marsden said he would be raising a “highly worrying series of failings” with health secretary Matt Hancock.
Mr Marsden spoke out after members of Blackpool Council’s adult social care and health scrutiny committee questioned Dr Leon LeRoux, clinical director at Lancashire Care, about the way mental health services are being run.
A lack of resources, including staff shortages and not enough beds, was blamed for the problems which led to the CQC giving Lancashire Care a ‘must improve’ rating.
A Lancashire Care spokesman previously said: “An improvement plan has been developed to address some of the fundamental issues in the delivery of mental health services and part of this involves looking at how we can increase capacity within services to respond to current demand.”