Two truck drivers have escaped injury after their vehicles collided at Douglas Park, south of Campbelltown, this morning.
The crash occurred around 11am and involved two trucks travelling in the same direction on the Hume Motorway.
Emergency services responded to reports of a BASE jumper in the area moments before the crash.
While a search of the area was not able to locate anyone, police are now calling for witnesses to come forward.
Anyone with information in relation to this incident to call Crime Stoppers on 1800 333 000 or use the Crime Stoppers online reporting page.