The mishap occurred yesterday near Godavari hotel when Aftab along with his wife, son and another woman relative was returning from Roorkee to Manglaur, they said.
The impact of the collision was so powerful that all the occupants of the two-wheeler landed several metres away from the vehicle.
They were rushed by the police to the civil hospital Roorkee where all the four were declared brought dead.
The driver fled leaving the car on the spot immediately after the accident, Manglaur police station sources said.