Ramnath Badri Yadav, the victim, was riding pillion behind his son Ajit on a motorbike on Vasai-Bhiwandi road when the driver-side door of a tempo ahead of them opened suddenly, hitting them. Both fell on the road.
While Ajit could get up in time, Ramnath was run over by a container truck which was coming from behind, said senior police inspector Ankush Akade of the Narpoli police station.
Yadav died on the spot, he said.
A case was lodged against the driver of the tempo who was yet to be arrested.