The incident happened on Monday morning, at 10:20am, on the A725 in Hamilton involving a white Mercedes van, a green Kia Picanto and a white Hyundai Kona.
The driver of the Kia Picanto sustained serious injuries and remains in a critical condition within the Queen Elizabeth University Hospital in Glasgow.
With the driver of the Hyundai Kona also having gone to hospital in Wishaw, University Hospital Wishaw, but has since been discharged.
The driver of the Mercedes van was uninjured.
Police are now turning to the public and appealing for witnesses of the crash, with Sergeant Andrew Coutts, Road Policing Unit, asking those who may have dashcam footage to come forward.
He said: “Whilst a number of people have come forward with information about the crash, we are still keen to hear from anyone else who witnessed what happened, or who may have dashcam footage of the incident.
“Details can be passed to officers via 101. Please quote reference number 0854 of Monday, 27 November 2023 when calling.”
