The mishap took place when the ill-fated vehicle fell into a deep ravine near Pandukeshwar between Badrinath and Joshimath, Chamoli SP P Renuka Devi said.
The victims, whose identity has not been established so far, were returning after paying obeisance at the Badrinath temple located at a height of 10,000 ft, the SP said.
The sacred portals of Badrinath dedicated to lord Vishnu were thrown open to public after the six month winter break at 4 am today.