The passenger is believed to have fled the scene on foot.
Fletcher said the woman may have been in her vehicle for up to two hours before being found by the security guard.
“I think the driver was semiconscious when located,” he said.
“We’re appealing for any public assistance for any information that they may know, or any dashcam footage of the Foxwell Road, Coomera area between 11pm and midnight (on Tuesday) night.”
Investigators have also recovered several items from nearby bushland - including what appeared to be a knife and a jar - but police are still working to confirm whether they are linked to the attack.
“We don’t know what’s contained in that jar at this point in time and we are conducting further inquiries into that,” Fletcher said.
He confirmed they are working with Uber and Westfield management to obtain CCTV footage.
“All stakeholders involved in this incident have all been forthcoming with police and assisting us with our inquiries, and they are ongoing,” he said.
The suspect has been described as a man in his late teens to early 20s with dark hair, who was last seen wearing a light green T-shirt with a motif on the front and grey tracksuit pants.
Fletcher said the stabbing appeared to be random, with no evidence so far the woman and passenger knew one another.
He stressed the community should not be fearful of booking rideshares.
“This seems to be an isolated incident that had nothing to do with the actual rideshare company,” he said.
Police towed the woman’s car for forensic testing and continue to canvass the area for evidence.
Fletcher said violent incidents were confronting for both the community and police.
“Any crime that has an element of violence is never acceptable in our society,” he said.
“QPS will always work tirelessly to bring those offenders to justice.”
A crime scene was established around the woman’s vehicle and the surrounding shopping centre precinct, with forensic officers and police dogs scouring the area.
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