Two women have been charged after a woman’s hand was spotted waving through a hole made in a car’s broken tail light as it drove in the NSW Southern Highlands.

Police will allege Kayley Lee Katley, 18, was at the wheel of the Holden Commodore with Latia Henderson, 24, in the passenger seat, driving on the Hume Highway at Pheasants Nest on Wednesday.

Unsuspecting fellow drivers may not have known there was a third woman in the car – stashed in the boot and suffering stab wounds.

A truck driver driving behind the Commodore noticed a hand waving out of a punctured tail light and alerted NSW Police.

Twenty minutes later, highway patrol caught up with the pair and the 24-year-old woman was extracted from the boot of the car at Berrima.

The woman was discovered suffering multiple stab wounds to her knee, thigh and forearm and taken to Liverpool Hospital in western Sydney.

Ms Katley and Ms Henderson were arrested and charged on Wednesday night with several violent offences and drug possession.

Ms Katley was charged with wounding a person with intent to cause grievous bodily harm, taking or detaining in company with intent to occasion actual bodily harm, taking and driving a conveyance without the consent of owner, driving motor vehicle during disqualification period and drug possession.

Ms Henderson was charged with wounding a person with intent to cause grievous bodily harm, taking or detaining in company with intent to occasion actual bodily harm, taking and driving a conveyance without the consent of owner and being an unlicensed person driving a vehicle on a road.

Kayley Lee Katley, left, and Latia Henderson. Photo: Supplied

On Thursday morning, Detective Chief Inspector Brendan Bernie said the three women met at a residence in Claymore on Tuesday night.

Early on Wednesday, the victim was allegedly stabbed and put into the boot of the car.

Investigations are ongoing as to where the pair were taking the injured woman.

“We will be alleging she was in the car for several hours before she was sighted,” Chief Inspector Bernie said.

He said the woman was discovered “with a fair amount of blood on her”.

Police are still investigating where the two women were taking the injured woman. Photo: Supplied

She remains in hospital and will undergo surgery today for her stab wounds which were “deep”, Chief Inspector Bernie said.

He said the truckie did an “amazing job” of noticing the hand and notifying authorities.

Ms Katley and Ms Henderson were refused bail and will appear in Picton Local Court on Thursday.

-ABC