CBI on Tuesday said it has started investigation into the murder of Congress councillor of Jhalda municipality, Tapan Kandu and will interrogate Purulia district superintendent of police in connection the case. The inspector in-charge of Jhalda police station is also likely to be questioned in connection with the murder which took place on March 13, a CBI official said here.

The slain councillor's wife, Purnima Kandu has been alleging involvement of the IC in the killing. He was fatally injured after being shot at by bike-borne assailants and succumbed during treatment. His wife had approached the Calcutta High Court for a CBI inquiry into the murder. The HC on Monday ordered a CBI investigation into the killing.

"We have started out investigation and will question Purulia SP, S Selvamurugan soon in connection with the murder of Tapan Kandu. We will also talk to other witnesses besides the MLA's family members. We have got the necessary documents regarding the probe from the investigating officers," a CBI official said.

Meanwhile, Kandu's family members on Tuesday came up with an audio recording of a conversation allegedly between him and another person, who they claimed to be a local leader of Trinamool Congress. The man is heard in the audio recording forcing the Congress leader to join TMC.

"We will give this to the CBI officers which will help them in their investigation into my husband's murder. We will fully cooperate with CBI," Purnima Kandu said. Earlier in the day, Jhalda witnessed protests by Congress workers, who took to the streets in a huge rally opposing the formation of Jhalda municipal board by TMC.

Congress supporters, mostly women, clashed with the police and broke barricades put up to stop them from marching to the municipality building, the venue for the formation of the board. Purnima Kandu, who too is a Congress councillor, entered the municipality and protested against the formation of the board.

Later, Congress called a 12 hour strike in Jhalda on Wednesday, Purulia district Congress leader Nepal Mahato said. The TMC had bagged 103 out of the 108 civic bodies in the Jhalda municipality of West Bengal.