The incident took place last night when Som Pal Singh tried to stop the accused, they said, adding that they ran the car over him in an attempt to flee.
The vehicle was later found abandoned on G T Road.
Singh has sustained fractures on his ribs and leg and his condition was stated to be critical till late evening today,
They said.
An FIR has been registered against four persons, all of whom are still absconding, they said.