Four motorbike-borne criminals used AK-47 assault rifles to gun down three persons including Manoj Kumar Sah, the nagar panchayat deputy chief councillor of Pakridayal, a sub-divisional town in East Champaran district, on Wednesday evening.

People staged a protest with the bodies on Thursday, demanding the immediate arrest of those involved in the crime. Shops remained shut through the day.

Manoj was a BJP leader. Others killed with him include local trader Chuman Kumar and Manoj's aide Subodh Kumar. Radhe Shyam Sah, another resident, received bullet injuries and is being treated at a private hospital.

Vijay Kumar, an eye witness, said: "The criminals fired around 20 rounds from a sophisticated weapon while their targets sat inside a foodgrain shop on Pakridayal-Sheikhpurwa road. They flung some pamphlets before fleeing. East Champaran superintendent of police Jitendra Rana said special teams are conducting raids to arrest the men. The motive behind the crime is not known. Suspect Sonu Pratap Singh from Rupahari village under the jurisdiction of Shikarganj police area is among those arrested for interrogation.

Sonu has a criminal record and has been wanted by police in several cases of extortion, added Jitendra. "We are also trying to unearth the actual motive behind the killing."

BJP leaders, led by Motihari MLA Pramod Kumar, also staged a dharna in Pakridayal chowk to protest, and claimed that law and order had hit a low in the state under the current government.