The incident took place when the bus carrying pilgrims was returning from Vidhyachal (Mirzapur) and collided with the stationary truck, killing four persons on the spot, they said.
Those killed have been identified as Shashikala (30), Dharmshala (60), Anita (30) and Ajay Sharma (28), they said, adding that the injured have been rushed to a hospital, where their condition was stated to be stable.