Monoghan General Hospital has been closed to emergency and elective surgery due to a lack of anaesthetists.
An action group in Co Monaghan says it is considering legal action against both the Minister for Health and the North Eastern Health Board to ensure the hospital is kept open.
Yesterday morning, patients, some of them elderly, were turned away after they arrived for surgery, unaware that surgical procedures had been suspended at the hospital.
In a statement, the North Eastern Health Board said it had a problem recruiting EU-registered hospital doctors or consultant staff for the hospital.
In relation to recruiting non-EU doctors, it must meet the requirements of the Medical Council and, in this situation, those of the College of Anaesthetists.
In addition, both these bodies must be satisfied that the hospital in question could provide doctors with an approved training and education programme.
The deputy chief executive officer of the North Eastern Health Board, Dr Ambrose McLoughlin, rejected allegations from politicians that this was the latest in a series of services to be suspended at the hospital, including the closure of the maternity unit in March 2001.
"We are not closing the hospital. We have a temporary problem, hopefully of short-term duration, related to our inability to recruit non-EU registered doctors," he said.
It is believed a last-minute issue led to the lack of anaesthetic cover from July 1st and the North Eastern Health Board issued a directive to all its consultants and heads of departments on Tuesday saying it was off emergency call, i.e. ambulance personnel would not take medical or surgical patients there.
It also cancelled all elective or planned surgery, but the short notice meant not all patients were informed before they arrived at the hospital yesterday morning.
However, a local alliance campaigning to maintain and restore acute services at the hospital said it is getting legal advice from a senior counsel this week on taking a High Court challenge against both the health board and the Minister to ensure the hospital remains open.
Its chairman, Mr Peadar McMahon, said the consultants in the hospital predicted the problem and the health board and Minister were told of it in March this year.
The alliance supported the campaign of newly elected TD Mr Paudge Connolly, who last night said he felt the executive of the board was ignoring board policy on the future of the hospital as detailed in its framework document, which was adopted unanimously by the board in June 1998.
Mr Connolly polled more than 7,700 votes in the general election in the Cavan/Monaghan constituency. He voted for Mr Bertie Ahern in the election for Taoiseach last month, even though other independent candidates who fought the election on health issues abstained or voted against Mr Ahern.