The body of a young man has been found in bushland in southwest Sydney.

The man, believed to be aged in his 20s, was found near the Georges River in Airds, southeast of Campbelltown, just after 5pm on Tuesday.

Detectives were called to Woolwash Rd, where a steep 1.6km fire trail leads back towards a nature preserve known as The Woolwash.

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A waterhole sits at the junction of O’Hare Creek and the Georges River.

It’s unclear exactly where in this bushland area the body was found.

It’s also unclear at this stage whether the death was suspicious, and police are investigating how the body came to be there.

The body is yet to be formally identified, NSW Police said.

Investigations are continuing and anyone with information is asked to contact Crime Stoppers.