Emergency Services have been called to a serious two vehicle crash at Marulan.
Around midday today, a Hyundai Sedan and a Toyota Corolla were travelling in the southbound lanes when they collided and crashed into trees on the median strip.
The male driver of the Hyundai suffered serious leg injuries and his male and female passengers suffered minor injuries.
Meantime a female passenger of the Toyota suffered serious head injuries.
The male driver of the Toyota wasn't hurt, but was taken to hospital under police guard for mandatory testing.
There's currently heavy traffic in the area.
IMAGE CREDIT: NSW Police