Two Goulburn Valley residents died in a crash at Rochester on Friday, July 5.
Emergency services responded to reports two vehicles had collided head-on on the Northern Hwy about 5km south of Rochester about 1.30pm.
A Mooroopna man, 65, who was driving one of the vehicles, died at the scene.
His female passenger, a Kyabram woman, 68, was extracted from the car and given medical assistance, but died at the scene a short time later.
The driver of the other vehicle, a woman in her 40s, was flown to the Royal Melbourne Hospital with upper body injuries.
On Monday she remained in hospital in a serious condition.
Two teenage girls who were passengers in that vehicle were taken to Bendigo Health, both with upper body injuries and lower body injuries, in a stable condition.
Police said the exact circumstances surrounding the collision are yet to be determined and investigations were ongoing.
The highway was closed in both directions while emergency services were on scene.
It reopened overnight Friday.
Anyone who witnessed the incident, has dashcam footage or any other information that could assist police is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au