A woman has died after her car left the road and hit a tree near Stirling.
The 28-year-old was discovered by a lorry driver who spotted a light from her vehicle next to the M9 at Cambusbarron on Wednesday night.
She was taken to Queen Elizabeth University Hospital in Glasgow but she died early on Thursday morning.
Sgt David Marr paid tribute to the motorists who stopped to help the woman after her silver Ford Fiesta was found at 22:30.
He said: "I cannot commend enough the HGV driver who saw a light from the vehicle and pulled over to investigate this further, before calling emergency services.
"I also want to thank the two other people who stopped to provide assistance.
"As part of our ongoing enquiries into this collision, I'd urge anyone who may have seen the vehicle travelling in the area between 22:00 and 22.30 to contact us as soon as possible.
"Those who have any other information which could be relevant, or who were travelling on the M9 around this time and have dashcam footage, are also asked to get in touch."
The accident happened between junctions nine and 10 of the M9 and the road was closed until 06:00 while investigations were carried out.