The incident occurred in yesterday afternoon when, in an attempt to save a biker, the truck driver drove to his right and the vehicle rammed into the bus, they said.
Preeti (8) and Honey (5) died on way to a hospital in Dehradun while the rest of the injured, including two women and four children, are undergoing treatment, they said.
The bus driver fled from the spot immediately after the mishap but the truck driver has been arrested, they added.