A 32-year-old man has been arrested as police investigate the death of a teenager found in bushland near Sydney’s southwest.

Emergency workers were called to an area of bushland off Wilton Park Rd at Wilton about 7.25am on Saturday after a witness found the body of a 15-year-old boy and called emergency services.

After a public appeal for information, police said the 32-year-old man was arrested after presenting himself at Narellan Police Station shortly after 4pm.

NSW Police said no charges had been laid and inquiries were ongoing.

Camden Police believe roughly a dozen young campers might have gathered on Friday evening near the area, where the body of the teenager was found the next morning.

Acting superintendent Tim Calman said the death was being treated as suspicious and state crime had been called to the location to help as there were “a lot of moving parts”.

“We believe something happened on the Friday evening,” he told the media on Saturday, but there was “nothing to indicate that there was any alarm raised last night”.

“I’ve no information to substantiate whether it was an altercation (with the alleged group) or an external party,” he said.

Mr Calman said police were following a number of active lines of inquiry but it was too soon in the investigation to say whether a weapon or vehicle was involved.

While the deceased was yet to be formally identified, police believed him to be a 15-year-old boy from the Wilton area.

His family had been notified, Mr Calman said, and were being supported by police after the “tragic” incident.

“We put our thoughts out to the family,” he said. 

“They will be doing it tough this afternoon.”

Police are appealing for anyone with knowledge of the incident or dashcam or mobile footage to come forward, as well as anyone who might have been in the area since 6pm on Friday.