The car's driver Akhilesh Lohia (36) was arrested from the spot. He was in an inebriated state at the time of the incident, they said.
Lohia was returning from a marriage party and was allegedly speeding. Constable Bhoop Singh, who was deployed at a police picket for checking vehicles, had signaled the driver to stop, the police said.
However, Lohia rammed into a barricade and also hit the police personnel, leaving him injured, they said.
The police said that Singh, was posted with the Vasant Vihar police station and was on night duty. He suffered a severe head injury.