Six persons died on the spot while four succumbed to injuries on way to the hospital, police said, adding, the death toll could rise as conditions of some was stated to be critical.
The state-run Himachal Road Transport Corporation bus was carrying 50 passengers from Shimla to Pahlog. The mishap took place when the driver tried to reverse the vehicle to give way to another bus coming from opposite side and fell into a deep gorge, police said.
Police said six bodies have been recovered from the spot and injured persons were extricated from the wreckage of the bus with the help of local people.