3pm UPDATE: All lanes of the Princes Highway have reopened between Wandandian and Bewong after an earlier car accident.
There are no delays to motorists in the area.
1.50pm: A 17-year-old girl has sustained a serious leg injury following a serious crash on the Princes Highway near Bewong, south of Nowra, on the South Coast this morning.
About 7.55am, a Toyota sedan travelling north collided head on with a Toyota 4WD travelling in a southerly direction.
The girl was driving the sedan at the time, and also sustained chest injuries.
The 50-year-old male driver from the other car also received leg and chest injuries.
Both drivers were trapped for about an hour before being airlifted to St George Hospital for treatment where they remain in a serious but stable condition.
Traffic is flowing slowly and has been diverted around the incident.
Road users are advised to delay all travel or take an alternate route.