Four women have died and another has been seriously injured when their car came off the road in regional Victoria.

The car was travelling along Wannon-Nigretta Road outside Bochara in the state's west when the driver lost control this morning about 9.30am.

The car then slammed into a tree.

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Four women in the car died at the scene.

A fifth has been taken to hospital with serious injuries.

Detectives from the Major Collision Investigation Unit are investigating the cause of the crash.

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The area has been cordoned off.

Bochara is a rural locality outside of Hamilton.

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