A VIOLENT convict who assaulted another prisoner in a row over a phone card was last night starting another jail sentence – for four years.

Matthew Stobie’s attack on fellow inmate Shane Watt left him brain damaged and led to the 36-year-old dying from pneumonia six months later.

Stobie, from Darlington, admitted manslaughter at an earlier hearing and was yesterday sentenced by Judge Peter Fox at Teesside Crown Court.

The judge told the 27-year-old: “The consequences of your action have deprived a family – young and old – of someone whom they dearly loved.”

Father-of-two Mr Watt was injured when he was punched by Stobie inside Holme House Prison, Stockton, on July 11 last year.

The court heard that he suffered a brain injury and underwent surgery, but never recovered and died in hospital on February 20.

Former roofer Stobie, of Lewis Road, Darlington, was serving a sentence of more than two years for burglary at the time of the attack.

Sarah Mallett, prosecuting, told the court that over Christmas 2009, both men were in the prison for other matters and shared a cell.

Mr Watt is said to have gained access to Stobie’s phone card Pin and used up all his credits – leaving him unable to call his children.

Stobie was still behind bars last summer when Mr Watt, from Brotton, east Cleveland, was remanded in custody after being arrested on a warrant.

The court heard how the two men clashed and Stobie punched Mr Watt when he denied being responsible for using his phone credits.

Stobie, who was a cleaner in the jail at the time, later told his girlfriend during a prison visit: “I’m f***ing sick. I only hit him about three times, at the end of the day, it’s an assault, not f***ing murder.”

Stobie was originally charged with inflicting grievous bodily harm, but following Mr Watt’s death, he was re-arrested and charged with manslaughter.

It is thought the victim may have struck his head on a wall or the floor as he fell.

Stobie’s barrister, Dan Cordey, told the court: “He apologises to the family of the deceased. He knows that cannot redress the harm he has done.

“The harm caused was certainly not intended and was out of all proportion to the actual assault.

It was a single punch thrown in the heat of the moment, resulting in a very, very tragic injury.”

Detective Inspector Chris Downes said: “Matthew Stobie was already serving a custodial sentence for burglary when this offence was committed.

"Today’s sentence sends out a clear message that regardless of where the offence is committed police will still take robust action to ensure justice prevails.”