UPDATE: Convicted killer who knifed his pal on the loose from Doncaster prison

Prison absconder Michael Robson.
Prison absconder Michael Robson.

Police are searching for a killer - who stabbed his pal to death 20 years ago - after he absconded from an open prison in Doncaster.

Michael Robson, aged 44, who is serving a sentence for manslaughter, left Hatfield Prison on Thursday, July 16, and has not returned.

The North Shields man was jailed two decades ago for stabbing his pal Robert Williamson to death while high on drink and drugs in June 1995.

Prison staff became aware he was missing at around 12.30pm and notified police shortly after. Officers have been carrying out extensive searches within the prison and the surrounding area to find him but he has not yet been located.

Around 20 years ago, Newcastle Crown Court heard how Robson was intoxicated when he killed 25-year-old Mr Williamson following an argument.

The hearing was told how minutes after stabbing him with a single blow to the chest, the then 25-year-old Robson used the same kitchen knife to slash open his own sister’s face.

He then went on the run and was not arrested until two weeks after the attack.

At the court hearing it was claimed he had been suffering a mental disorder triggered by depression and grief at the loss of four close family members.

The jury found him guilty of murder and wounding with intent, and he was jailed for life. But in 2006 the murder conviction was overturned by the Court of Appeal and reduced to manslaughter.

At the time, Mr Williamson’s sister Allison Williamson, then 30, said: “He deserved his life sentence then and he deserves it now.”

Robson is described as white, around 5ft 9ins tall, of stocky build and has brown hair.

A spokesperson for South Yorkshire Police said: “Have you seen him or know where he could be?

“If you see Robson, you are advised not to approach him but to call South Yorkshire Police on 101, quoting incident number 543 of 16 July 2015. “Where there is imminent risk or danger, always call 999. Alternatively, call Crimestoppers anonymously on 0800 555 111.”