A police officer and another motorist have died overnight in rural Victoria, while another police officer remains in hospital in a critical condition.
Police said it appears the unmarked police car and ute were travelling in opposite directions on Kulkyne Way in Red Cliffs, south of Mildura, when the two vehicles collided around 10pm.
The ute is believed to have veered into the path of the police vehicle, Chief Commissioner Shane Patton said at press conference on Saturday morning.
A third vehicle was also involved in the collision.
A female senior constable and the male driver of the ute died at the scene.
Chief Commissioner Patton said the female police officer was just 25-years-old and from Mildura Highway Patrol.
"It is a tragedy and absolutely heartbreaking," he said.
The female officer was driving the unmarked police vehicle at the time of the crash.
Her colleague, a 43-year-old male leading senior constable suffered critical injuries.
Comm Patton said the 43-year-old was initially taken to Mildura Base Hospital, before being airlifted to Melbourne, where he is in a critical but stable condition.
The Commissioner said the major collision unit is now investigating the incident.
"I can say at this stage, there is no indication of any attempt by the police vehicle to be intercepting anyone, no pursuit involved," he told reporters.
"The preliminary investigation, as I say, appears that for whatever reason, the other vehicle has veered into the police car."
The third vehicle involved collided with the police vehicle from the rear.
Two adults and three young children were in the third vehicle and were taken to hospital for assessment.
The coroner has been notified and because a civilian was killed, Victoria's Professional Standards Command will oversee the investigation.
Comm Patton said the deaths will have a substantial impact on the community and police force.
"No-one expects to go to work and not come home," he said.
"Our hearts go out to all of those family and friends of all deceased persons. Our hearts go out to our police colleagues.
"This will be especially difficult, attending a fatal collision is a difficult thing for any police officer to do."
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