The accident took place around 1.30 AM near Mehrauli- Badarpur Border area when Shish Ram, on duty at CCI in Tughlakabad Village in southeast district, was crossing the road to take tea from a vendor on the other side, said a senior police officer.
As Ram was crossing the road, an over-speeding truck hit him in his leg, the officer said, adding another policeman accompanying him had a close shave.
The policeman accompanying Ram informed the police control room and a team was sent which moved the injured to AIIMS Trauma Centre.
Ram has been posted at the Govindpuri police station since July 25, 2014.
The driver fled the spot leaving behind his vehicle but was arrested later, said the officer. The driver has been identified as Rahisudeen.
A case under sections 279 of IPC (rash driving or riding on a public way) and 338 of IPC (causing grievous hurt by act endangering life or personal safety of others) has been registered at Pul Prahladpur police station, he added.