The driver, who suffered head injuries, and the front seat passenger, were treated at the scene for multiple injuries by paramedics, before being taken to hospital.

One 29-year-old woman is in a serious condition, while the other, a 52-year-old woman, remains stable.

It is believed the Honda Civic crossed to the wrong side of the highway at 5.20am and rolled a number of times.

Emergency services stayed on the scene, redirecting traffic into the northbound lanes throughout the morning.