Police are appealing for help to trace a convicted murderer who escaped from Pentonville prison yesterday.

John Massey, 64, made off from the Islington prison at around 6.30pm.

He is considered potentially dangerous and police are warning the public not to approach him if he is seen.

Massey, a former carpenter, was sentenced to life imprisonment for the murder of a man at the Cricketers public house in Cricketfield Road, Lower Clapton, in September 1975.

It was said to be a revenge raid after after two other men were thrown out of the pub after a fight.

Massey, who lived in Castle Road, Kentish Town, was also convicted of attempting to murder a police officer.

In 1976 it was recommended he serve 20 years before parole.

If you see Massey, call 999.

His hair is greyer than the image available.

Anyone with information on his whereabouts is asked to call Islington Police 0207 421 0296; if to remain anonymous call Crimestopppers on 0800 555 111.