AN inquiry will be held into how a convicted killer dubbed the Black Dog Strangler escaped from a secure hospital, health trust bosses said today (Thursday, January 3).

Phillip Westwater, 44, now known as Whiteman, left his clothes in a pile at St Nicholas Hospital, Newcastle, after asking to use the toilet during an escorted visit within the site yesterday (Wednesday, January 2), then disappeared for 12 hours.

The twice-married patient, who was detained indefinitely under the Mental Health Act after paralysing a man during a pub fight in 1989, was reportedly found in a bar in the city centre's gay area after a member of the public recognised him from a photo circulated by the media.

A year after Whiteman was held for the pub attack, he killed a fellow inmate at Liverpool's Ashworth Hospital with his dressing gown cord, convinced his victim had turned into a black dog. He admitted manslaughter on the grounds of diminished responsibility.

Northumberland Tyne and Wear NHS Foundation Trust runs a medium secure unit within its St Nicholas site, and said Whiteman escaped during an escorted visit to a restaurant in another building.

He asked to use the toilet, from where he vanished, leaving a pile of clothes on the floor.

A trust spokesman said: "The trust takes public and patient safety extremely seriously and always strives to provide safe and therapeutic care for patients whilst minimising risks in relation to absconsion.

"Planned or escorted leave is an important part of any patients treatment plan, especially when working towards their recovery.

"Arrangements for escorted leave are rigorously risk assessed, made on an individual basis and regularly reviewed.

"The decision to grant leave involves the views of the patients multi-disciplinary clinical team and when appropriate input from the patient, their carers, family members, as well as external agencies such as the police and Ministry of Justice.

"We have strict protocols and procedures in place around managing episodes of escorted leave but we can always learn from individual incidents such as this.

"We will be carrying out a thorough internal review of this incident as soon as our colleagues at Northumbria Police have concluded their investigation."

Whiteman married a nurse while he was a patient at high-security Rampton Hospital in 2008.