Emergency services in Northern Ireland are reaching crisis point with staff unable to cope with the number of people turning up for treatment at A&Es, it has emerged.
A leading nursing union has called for health bosses to take urgent action after staff at some casualty units were asked to discharge patients and cancel operations in order to free up beds.
It is also understood the Northern Health & Social Care Trust has written to GPs asking them to refer patients from Newtownabbey to the A&E at the Mater Hospital to ease pressure on Antrim Area Hospital.
Figures released by the Northern Health & Social Care Trust showed 730 people waited longer than 12 hours at the casualty unit at Antrim Area Hospital between December 1 and January 12 - an average of 17 patients each day.
Meanwhile, figures from the South Eastern Health & Social Care Trust reveal 511 people waited longer than 12 hours and 2,224 people waited longer than four hours at the Ulster Hospital A&E last month.
They also show that 500 more people turned up at the A&E compared to the same period last year and the closure of the casualty unit at the City Hospital has been blamed for the rise in attendances.
The problem has arisen just weeks after Health Minister Edwin Poots said hospitals were coping well following the closure of the A&E at Belfast City Hospital.
Director of the Royal College of Nursing (RCN) in Northern Ireland, Janice Smyth, said the current situation is "unacceptable" and said unions had warned hospitals would struggle to cope in light of recent changes to emergency services.
"We were concerned this would happen following the closure of the A&E at Belfast City Hospital and management assured us at the time they had taken appropriate steps to make the service safe and sustainable. Sadly, that does not appear to be the case.
"We understand that there are particular winter pressures, such as norovirus, but that should not come as a surprise. Our nurses would tell us patients are backed up on trolleys and they are concerned about their ability to do their job."
One man, whose wife was taken to the Ulster Hospital A&E by ambulance last weekend after she developed breathing difficulties, said: "When she got to the entrance there were five other ambulances in front waiting to get patients inside.
"It was about an hour before she was actually taken in to A&E. The staff there were run off their feet, but doing a remarkable job.
"When I remarked on how busy it was, they said it was actually normally worse. They said they couldn't cope after the City Hospital A&E closed."
There was anger when health bosses announced the closure at Belfast City Hospital with concerns raised A&Es in and around Belfast would struggle to cope. Health Minister Edwin Poots said the changes had improved the speed at which patients were moving through A&Es at the Ulster, Royal and Mater hospitals. There have been waiting problems at Antrim Area Hospital for years, but health chiefs insist the situation will improve when the new A&E is built.