A man who was found collapsed at a South Yorkshire Park yesterday morning died as a result of a heart attack.
South Yorkshire Police launched a murder investigation after they discovered an injured 65-year-old man in Hexthorpe Park, Doncaster, at around 4.40am on Tuesday.
The man was rushed to hospital but could not be saved and was pronounced a short time later.
A post-mortem examination into his death has today concluded that he died as a result of a heart attack.
Police said that further tests and enquiries are continuing into the full circumstances of the incident.
A 17-year-old boy and and an 18-year-old woman, who were arrested yesterday on suspicion of murder have been released from custody.
Anyone with information should call South Yorkshire Police on 101 quoting incident number 103 of 18 April 2017.