There was a large trail of blood leading to where a man lay dying at St Clair in Sydney’s west on Tuesday afternoon, New South Wales Police say.

Officers were called to a house at Wills Glen about 12:30pm and said they found a man they believe to be 20 to 25 years old with head injuries.

• Stephanie Scott’s remains identified
• More Aussie troops head to Iraq

It is believed the man was trapped between a wall and a fence of a vacant house that is up for lease.

Superintendent Greg Peters said despite attempts to revive the man, he died at the scene.

Police have appealed to the public for information about the incident and Superintendent Peters said it is unclear what happened at this stage.

“There’s a large amount of blood that goes right through to the park behind the house up the end of the street and that’s all I can say at this point in time,” he said.

Officers are treating the death as suspicious.

Superintendent Peters said forensics experts were examining the area.

“We are treating it as a suspicious death at this point in time but we have no further information about how the injuries occurred … or where the injuries occurred or any other information in relation to that,” he said.

The man has not been identified and a report will be prepared for the coroner.