Relatives of a man who was found dead in the middle of a road in Melbourne's west are pleading with the driver to turn themselves in to the police.
A passing driver found Aaron Brown, 27, lying in the middle of Boundary Road between William Angliss Drive and Mt Derrimut Road at Derrimut just before 3.50am today.
Police believe he was struck by a silver Holden Rodeo towing a trailer as he crossed from the north to the south side of the road.
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Police said the driver dumped the vehicle at the scene and was believed to have either left on foot or been picked up by another person.
They said the ute was unregistered and the number plates didn't match the description of the vehicle.
Brown's family is pleading for the driver involved to come forward.
They described Brown, who had autism, as a beautiful, kind-hearted boy who loved playing chess, video games and listening to music.
"We're devastated, he should have never been where he was," said his sister Kaela Brown.
"He was so innocent."
Police said it was unclear what Brown was doing on Boundary Road in the early hours of the morning.
Witnesses in the area told 9News he appeared disoriented in the hours before he was found.
"It's a heartless and cowardly act if, you know, someone is deceased on the road," said Detective Senior Sergeant Chris Alexander.
"For whatever reason has left the scene, they have a story to tell and they'll be actually going to come straight away and into the police station," he said.
Police have urged anyone with CCTV or dash cam footage to come forward.