A driver is missing but believed to be badly injured after a serious crash which split their vehicle in two in Melbourne’s west on Tuesday.

A passing motorist found the wreckage of a car — but no driver — about 1am and called emergency services.

The Toyota Kluger was crumpled into two separate pieces after smashing into a tree in Seabrook.

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Police said the car had been “totally destroyed” and believe it was travelling at speed before the driver unsuccessfully negotiated a roundabout, struck a gutter and crashed into the tree.

Police sniffer dogs were brought in to help find the driver, who is believed to have left immediately after the impact and has yet to be found.

“Officers hold serious concerns for the welfare of the driver who is believed to be a young man,” police said.

“A thorough search of the vehicle and the immediate area surrounding the crash has failed to find the driver who police suspect would be injured.”

The Kluger is believed to have been stolen about five minutes before the crash in a carjacking at nearby Laverton railway station.

The car was split into two pieces in the crash. Credit: Victoria Police

The hunt is still underway for the driver, who police believe to be injured. Credit: 7NEWS

Police said Protective Service Officers patrolling the railway station area raised the alarm after a man reported he had been pulled from his vehicle by another man, who then drove away at speed.

The driver, or anyone who witnessed the crash, is urged to come forward.

Investigations surrounding the carjacking and crash are ongoing.