Patients suffering acute psychiatric illness are having to endure more than three days on trolleys in one of the country's most overcrowded hospital emergency departments.
The escalating crisis led to a series of frightening episodes in the congested A&E at Beaumont Hospital in the last fortnight.
Internal correspondence obtained by the Irish Independent details how staff no longer feel they are working in a safe environment.
So far this month at the hospital:
A psychiatric patient tried to stab a care assistant.
Terrified patients watched as a person tried to slash their own wrists while making obscene comments about children.
One patient was left 78 hours without their medication.
A mother and daughter from the US were told they would have to wait for 24 hours in psychiatric A&E even though a bed was available at another hospital.
Gardaí were called to locate a patient who disappeared without treatment.
In an email to Beaumont CEO Liam Duffy, the hospital's Head Clinician in Emergency Medicine Peadar Gilligan said the victim of one attack was a newly appointed care assistant who "was almost stabbed by a psychotic patient and, had it not been for the bravery of one of the Emergency Medicine Registrars in coming to his assistance, the outcome could have been much worse".
It is understood that the patient chased the staff member with scissors.
Another memo signed by some nursing staff at the A&E said the situation was "harmful for patients".
Sources said the nine psychiatric patients were being cared for in the A&E last weekend.
Psychiatric patients who are in an acute state of anxiety or potential psychosis are treated in the already overcrowded A&E because there is no out-of-hours assessment unit in the hospital's Ashlin Centre, where people with mental illness are cared for.
During the month of May, there were 782 patients on trolleys in Beaumont.
Dr Gilligan confirmed last night that there is "huge concern" among staff.
The 38-bed Ashlin centre opened in May last year, replacing the long-running service in St Ita's, Portrane.
"It is now a huge issue. It also means that a large number of staff may have to take care of the psychiatric patient and there are not enough to look after the other patients.
"It is a huge concern to us and there is a serious risk of a violent incident," he said.
A spokesperson for Beaumont Hospital has said the Ashlin centre is under the control of the HSE, "with which Beaumont is working closely".
The emergency department has 24-hour security.
The HSE said the Ashlin centre provides acute inpatient care for the catchment population of north Dublin.
"It is acknowledged that there has been considerable demand for acute beds in the centre over the past number of months.
"However, every effort is being made to provide appropriate services for acutely unwell patients with mental health difficulties."