Convicted killer known as the 'Black Dog Strangler' on the run after escaping from secure mental hospital by asking to use toilet

Deranged murderer Phillip Westwater, dubbed the Black Dog Strangler, has escaped from a secure psychiatric hospital in Newcastle.

The murderer duped guards at St Nicholas Hospital in Newcastle after pretending that he needed to use the toilet.

The 44-year-old was detained indefinitely under the Mental Health Act in 1989 following a pub fight in which he left a drinker paralysed after slashing him across the throat.

He then strangled fellow patient Derek Williams at Ashworth Hospital, Liverpool, with his dressing gown cord after becoming convinced that the his victim had turned him into a dog.

The incident led to Westwater, originally from Newcastle, being given the nickname Black Dog Strangler.

At his trial Westwater admitted manslaughter on the grounds of diminished responsibility, with the judge saying: 'You are clearly very dangerous.'

Northumbria Police warned members of the public not to approach Westwater.

Westwater left the clothes he had been wearing in the hospital, considered a medium security unit, so officers are uncertain what he is wearing.

A police spokesman said: 'Officers are making inquiries into this individual and any risks he may or may not pose.

'In the meantime people are asked to contact police on the 999 emergency number if they see him and not to approach him.'

The killer, who is described as white, six feet tall, of slim build with brown/grey hair, escaped form the hospital at around 10am today.

He has previously been detained at high security psychiatric hospital Broadmoor, joining high profile prisoners such as Ian Brady.

Westwater has also been detained at Rampton Secure Hospital, Nottinghamshire.

Westwater's life in detention has not been without incident. He married fellow patient Susan Scott at high security hospital Broadmoor but they divorced in 2000.

Westwater then began a secret romance with a nursing assistant Claire Dudley who worked on his ward at Rampton high security hospital in Nottinghamshire.

The pair reportedly wed at a social club in the hospital in November 2008.

Nottinghamshire Healthcare NHS Trust said the right to marry was enshrined in the 1988 Human Rights Act.

A hospital spokeswoman denied the couple could consummate their marriage while he was being treated there.

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