A 26-year-old woman sub-inspector of the Delhi Police was shot dead near Rohini East Metro station on Friday night, officials said.
The SI, Preeti Ahlawat, was posted in Patparganj Industrial Area Police Station, police said.
A call about the incident was received around 9.30 pm, they said, adding she received gunshot wounds on her head.
"We have identified the suspects and CCTV footage of the area has been collected," said SD Mishra, Additional Commissioner of Police (Rohini).
Three empty cartridges were found from the spot, the officer said, adding a case has been registered and a probe is on.
Personal enmity is suspected to be the reason behind the killing, the officer said.
Ahlawat joined the Delhi Police in 2018.