The mishap took place yesterday when the driver lost control over the ill-fated vehicle and it turned turtle. Later, it caught fire, leading to the death of four of its occupants, they said.
The deceased have been identified as patient Soni (31), her husband Pradeep Kumar (38), sister Moni (25) and driver Nasir Ali (25).
Meanwhile, Ashwani, who also sustained serious injuries in the incident, was admitted to hospital, where his condition was stated to be critical, police added.