The accident occurred on Rishikesh-Badrinath highway when a huge boulder fell from the hillside on the 18-seater mini bus at Baspur between Chamoli and Karnaprayag this afternoon, district Disaster Management officer Nandkishore Joshi said.
Two persons in their thirties who hailed from Joshimath were killed on the spot while three others were injured out of whom one is said to be critical, he said.
The injured have been admitted to the district hospital Chamoli, Joshi said.