Paramedics have treated a truck driver for various injuries after a two-truck crash that has closed the southbound lanes of the Hume Highway at Blair Athol, near Campbelltown this morning.
NSW Police did not have any information about the condition of the other truck driver. One of the trucks was engulfed in flames.
Fire and Rescue NSW officers are working to extinguish the blaze.
NSW Ambulance later reported that one man in his 40s was taken to St George Hospital, and three other patients were treated for minor injuries at the scene.
Drivers are being asked to avoid the area, but anyone already on the motorway can exit onto Campbelltown Road and can then continue to Moore Oxley St and Narellan Rd to return to the Hume Highway. This is suitable for all vehicles.
Police said no further information is available at this time.
As inquiries continue, anyone who may have witnessed the incident or has dashcam or CCTV footage is urged to contact Crime Stoppers on 1800 333 000.
For the latest on the road conditions in the area, click here.