The double fatality occurred when a white Hyundai wagon travelling east on the Hamilton Highway collided with a west-bound maroon Mitsubishi at about 3.15pm.

The 56-year-old Bannockburn woman driving the Hyundai sustained life-threatening injuries and was trapped in the vehicle.

She was airlifted to hospital where she remains in a critical condition.

Her 25-year-old Bannockburn rear seat passenger was also airlifted to hospital with serious injuries.

She remains in a serious but stable condition.

A nine-month-old baby boy, who was in a child restraint in the back seat of the vehicle, was uninjured.

The investigation remains ongoing and anyone who witnessed the collision or saw the vehicles just prior to the collision is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au

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