Two people have died following a head-on collision on the Hamilton Highway on Friday.
Police and emergency services are still on the scene of the fatal collision which occurred in Cressy about 3.15pm.
Police said a white Hyundai wagon travelling on the Hamilton Highway collided with a maroon Mitsubishi about 3.15pm.
Both occupants of the Mitsubishi, who are yet to be formally identified, died at the scene.
The female driver of the Hyundai sustained life threatening injuries and was trapped in the vehicle.
She has been airlifted to hospital.
Her female rear seat passenger has also been airlifted to hospital with critical injuries.
A 9-month-old baby who was in a child restraint in the back seat of the vehicle was un-injured.
"There is major traffic diversion in the area and motorists are urged to avoid the area where possible," Warrnambool Police Sergeant Blake Amos said.
Traffic is being diverted from the Hamilton Highway between Urchers Road and Ballarat-Colac Road until further notice.
The investigation remains ongoing and anyone who witnessed the collision is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au.
The tragic incident brings this years' road toll to 125.
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