Anupam Dutta, a Trinamool Congress (TMC) councillor, was shot dead in West Bengal's Panihati municipality on Sunday, 13 March, NDTV reported.
Dutta was rushed to the hospital with severe head injuries, but was declared brought dead by doctors. The incident was caught on camera and the alleged killer, Shambhunath Pandit, was arrested based on the video footage.
Bharatiya Janata Party (BJP) MLAs protested against the incident in the state Legislative Assembly on Monday.
The incident occurred in Agarpara's North Station Road, according to the police.
Dutta was the councillor for Ward number eight in Panihati municipality of the state's North 24 Parganas district.
Manoj Kumar Varma, Commissioner of Police, Barrackpore, said that Dutta was being interrogated, and that more arrests are likely to follow.
According to police reports, Pandit had been hired as a contract killer to assassinate Dutta.