Police investigating the death of a man whose body was found in hospital grounds said the victim was not thought to be a patient or member of staff.
Police are hoping for clues from CCTV used in the grounds
The man, who has not yet been identified, is believed to have been killed by a gunshot to the head.
A spokesman for Rochdale Infirmary said the body was found early on Sunday, about 400 yards from the main entrance.
Greater Manchester Police said on Sunday they were no longer treating the death as suspicious.
A police spokesman said a post-mortem examination showed the man died of a gunshot wound to the head.
"Police believe they know the identity of the man and officers are in the process of contacting his next of kin but a formal ID has yet to take place."
The infirmary spokesman said the hospital remained open as usual.