A man has been arrested on suspicion of murder following the death of a 43-year-old man at HMP Doncaster.
The victim was allegedly assaulted at the prison at around 6pm last night (Friday 27 February).
He was taken to hospital, where he later died.
A 25-year-old man has been arrested on suspicion of murder and remains in police custody.
A post-mortem will be carried out today. Formal identification of the victim has not yet taken place
A spokesman for the prison service said Â ” A prisoner at Hmp Doncaster was taken to hospital where he died Â it is now a matter for the police”