The deceased were identified as the truck driver Rattan Singh (48) and one Roshan (28), both residents of Nainidhar, police said.
The injured, including three girls, were students of a local government who had taken lift in the truck. They were taking to a hospital for treatment.
While Sneha (12), Nikita (9) and Arushi (8) were taken to a hospital in Shillai, Ankit (21) sustained critical injuries and was rushed to Paonta Sahib for treatment, they said.
A case has been registered and investigation is underway to ascertain the cause behind the mishap, police said.