She is now terrified to go near the hospital for follow up treatment because of her ordeal which has left her devastated, she told the 'Journal'.

Bridie Cleere, from Ballymagroarty, said she was attacked on Sunday night after stepping outside for a cigarette at the casualty entrance to the hospital.

The 34-year-old said a man approached her, grabbed her arm and shook her until an approaching ambulance frightened him off.

Bridie said: "I was going down to get a smoke outside casualty. I couldn't walk very far because I had a catheter in. A fella approached me out of nowhere. He grabbed my arm and shook me that hard and he wouldn't let go. I shouted at him to let me go and that he was really hurting me but he just laughed at me and said something that I couldn't understand. I started crying and shaking. There was a woman there as well and I started roaring that he was hurting me.

"He then let go and grabbed my leg and pushed me against the wall; only an ambulance came and he saw it. I was so badly shaken up I couldn't breathe and took an asthma attack and needed oxygen."

Police were alerted to the scene and CCTV cameras were checked for the incident. A man was arrested and later released on police bail.

Bridie said she's been left badly shaken. She said: "I couldn't find security anywhere. It shouldn't happen to staff but especially not to patients. Security should have been there but they weren't. I was just devastated that something like this could happen at hospital where you are supposed to be safe."

A spokesperson for the Western Health and Social Care Trust said: "The Trust is concerned that patients or visitors to any of its health care facilities would experience threatening behaviour. The Trust takes the matter of security very seriously and deploys portering staff, with security duties, within the hospital and has Closed Circuit Television Cameras in operation in key areas including Accident & Emergency.

"The Trust can confirm that an incident has been reported and recorded in which a female patient was approached by a male outside the entrance to the A&E Department on Sunday night, May 4.

"CCTV footage recorded at the time has been passed to the PSNI and the Trust will assist the PSNI with their investigation."