The inmate found dead at HMP Lindholme in Doncaster last weekend has been formally identified as 22-year-old Michael Hennessy, who came from Nottingham.
A post-mortem examination has determined that he died from a stab wound. It is not yet clear what caused the injury.
South Yorkshire Police were contacted by prison officials at around 3.50pm on Saturday afternoon and informed of Mr Hennessy’s death, since which time officers have been conducting an investigation.
Two men aged 23 and 26 who were arrested by police in the prison on suspicion of murder on Saturday evening are on police bail but have been returned to the Prison Service while the investigation continues.