An inmate has admitted killing another prisoner in a South Yorkshire jail with a single punch.
Keiron Simpson, 26, has pleaded guilty to manslaughter at Sheffield Crown Court.
He was serving a prison sentence for burglary at HMP and YOI Doncaster when he attacked and killed Robert Bryan, 43, on Friday, February 27, 2015.
At around 6pm, Simpson approached Bryan, who was from Rotherham, while they were in the communal area of the prison.
He walked up to him from behind and punched him once to the face, knocking him to the ground. Bryan became unconscious and was taken to hospital, where he was pronounced dead the same evening.
A post mortem found the cause of death was a blow to the head.
Simpson will be sentenced on Tuesday, May 26.
Simpson, formerly of Smithywood Lane, Dodworth, Barnsley, was serving a 16-week sentence for burglary when he attacked his victim.
Bryan had been recalled to prison to serve out the remainder of a manslaughter sentence.
Detective Sergeant Andrew Knowles, investigating officer, said: “This case clearly shows how dangerous and devastating just one punch can be.
“Simpson attacked Bryan for no apparent reason – he may not have intended to kill him but anyone who makes the decision to strike another with force must consider the potential shattering consequences a single punch can have.
South Yorkshire Police will thoroughly investigate the circumstances of unlawful deaths, whether it occurs inside a house or inside a prison.”