An assistant sub-inspector of police was arrested in Jamshedpur in Jharkhand on Monday for allegedly killing his girlfriend by crushing her head and then strangulating her, a senior police officer said.

Dharmendra Kumar Singh, 39, who was posted at the Sakchi police station, allegedly killed Varsha Patel and dumped her body in a pond, said Subhash Chandra Jat, the superintendent of police (city).