A killer serving a life sentence stabbed another prisoner with a screwdriver for throwing away his food.
Steven Branscombe attacked the fellow inmate at HMP Full Sutton while in jail for murdering chef Marc Clarke in Bebington.
The 51-year-old was convicted in 2012, at Liverpool Crown Court, of stabbing 42-year-old Mr Clarke to death.
Eight years into his 23-year term, Branscombe assaulted another man in jail after "ill feeling" had grown between them.
Prosecutor Nigel Clive told Hull Crown Court that problems had begun when the victim threw away some of Branscombe's food.
The pair were in a workshop making bikes to be sold for charity when Branscombe approached the man from behind and stabbed him in the back of the neck with a screwdriver.
According to Hull Live, the victim was left with a 5mm wound.
Branscombe, a former soldier, was sent behind bars following a decade-long feud between himself and Mr Clarke.
The pair had reportedly fallen out over the quality of cocaine Mr Clarke had sold Branscombe.
Branscombe claimed he was the victim of attacks, threats, and acts of intimidation for a decade until he "snapped" on January 27, 2012 when he saw Mr Clarke driving.
He swerved his car into the victim's and then stabbed him twice with a six-inch kitchen knife he kept in his car.
Scores of witnesses, many of whom were on their way to or from school to pick their children up, watched in horror as Branscombe then got back in his car and drove away.
He was ordered to serve at least 23 years behind bars before being considered for release by the parole board.
Speaking about the incident at HMP Full Sutton in November last year, Mr Clive said: "It was a short-lived incident."
Branscombe represented himself during the short hearing, but told Recorder Barnett he did not have anything further to add.
He appeared in the court via videolink from HMP Frankland in Brasside, County Durham.
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On Tuesday [Dec 15], Recorder Barnett jailed Branscombe for 32 months, to run concurrently with his existing sentence.
Recorder Barnett said: "You pleaded guilty at the first available opportunity to this serious charge of attempting to cause wounding.
"I have no doubt that if things were different this could have caused a really serious injury.
"The fact is that you managed, during this manoeuvre, to cause a man injury.
"The reality is that this was a scratch and you have showed remorse and have conceded that you could have dealt with this in a different manner."
