A resident at a psychiatric hospital in Waterford has said she witnessed a woman being repeatedly stabbed in 2014.

Paul Cuddihy - who was a resident in the hospital at the time - has pleaded not guilty to murdering Maria O’Brien by reason of insanity.

Ms O’Brien died after allegedly being stabbed more than 100 times in St Otteran's Psychiatric Hospital in 2014.

Staff nurse, Mary Grant was on duty on the day of the stabbing. She said she gave Paul Cuddihy some anti-psychotic medication at around 5pm.

The court heard he has a history of paranoid schizophrenia.

She said she later took a call to say he was attacking Maria O’Brien in one of the on-site houses for residents.

She heard screaming when she approached the front door and set off her personal panic alarm.

When she went into the kitchen, she said saw Mr. Cuddihy standing over Maria O’Brien - who was lying on the floor covered in blood.

She said she asked him to put the knife down and was met with a fixed stare. She said he then turned on fellow staff nurse Breda Fennelly.

Terry Hayes - Assistant Director of Nursing at St. Otteran’s - said he was physically assaulted by the accused after going up to the house to see what was going on.

He said the kitchen area was “in turmoil” with furniture upended.

He told the court that Mr Cuddihy was covered in blood and had lunged at him a number of times. He said they wrestled in the house before he managed to make his escape.

Following Mr Cuddihy’s arrest, an armed Garda accompanied Mr Hayes back up the unit where they found Maria O’Brien slumped on the ground in an alcove near the staircase.

Paul Cuddihy denies the murder by reason of insanity. He is also charged with causing serious harm to Breda Fennelly and charges of assault causing harm to Mary Grant, Terry Hayes, and fellow resident Mary Nugent.