A man is being transported to hospital following a serious accident between two trucks at Mount Annan this morning.
Emergency services were notified of the incident between the two B-double trucks about 8.15am, near the Jim Affleck bridge close to Narellan Road.
One lane of the Hume Motorway has been closed in the northbound direction.
A 60-year-old, the driver of one of the trucks, was trapped and needed to be "extricated from the vehicle", a NSW Ambulance spokesman confirmed.
Once freed the man received treatment at the scene and is now being "transported to Liverpool Hospital via road accompanied by a specialist media team".
His injuries are believed to be minor at this stage.
The other man involved in the accident, the 26-year-old driver of the second truck, was also treated by emergency services at the scene and did not sustain any serious injuries, NSW Police reported.
There are significant traffic delays on the road because of the incident, with heavy traffic queued for up to seven kilometres.
A heavy-vehicle tow truck is in attendance.
Motorists are advised to allow extra travel time and exercise caution on the road.
Both north and southbound lanes were initially closed after the accident, but only one remains close now (10am) as the salvage operation continues.
Get the latest traffic updates at livetraffic.com.