Dipak Kandu, the nephew of Jhalda Congress councillor Tapan Kandu who had been shot dead on Sunday, was arrested on Tuesday in connection with the murder.

Dipak had contested against Tapan as a Trinamul Congress nominee from ward 2 of the Jhalda municipality in the recent polls. A probe has been ordered against Sanjib Ghosh, officer-in-charge at Jhalda police station, for his alleged links to the murder.

In connection with the murder of the Trinamul Congress’s Panihati councillor Anupam Dutta on Sunday, police arrested a real estate promoter on Tuesday.

A new complaint lodged by Tapan’s wife, Purnima, against Ghosh was incorporated in the original FIR.

Jhalda police admitted for examination an audio clip in which a voice similar to that of Ghosh was heard, asking a man to persuade Tapan to lend his support to Trinamul in exchange of vice-chairmanship at the civic board.

Tapan’s wife, Purnima, alleged that the police “knew well” of their own involvement.

“They are trying to find ways to save themselves. I want a CBI probe to know the truth,” she said.

Barrackpore police commissioner Manoj Verma confirmed the arrest of one more person in connection with the murder of Dutta.

He is Sanjib Mondal, a promoter from Panihati who is a maternal cousin of suspected killer Amit Pandit. Mondal has been picked up from a relative’s house in East Burdwan’s Kalna. The police have also detained another relative of Pandit from Kalna for interrogation.

“It is difficult to believe that even after 48 hours of the murder and the arrest of a killer, the police have achieved no breakthrough,” said Dutta’s wife Meenakshi, expressing her desire to meet chief minister Mamata Banerjee over the issue.

Mondal, said sources, harboured enmity towards Dutta over real estate.

“Dutta had recently demolished a boundary wall built by Mondal around a plot, to which he had objections,” said a police officer.

While quizzing Pandit, the police came to know that persons with enmity towards Dutta had appointed a Nadia-based sharpshooter in November last year.

“The sharpshooter, despite accepting the assignment, was dithering. That caused nerves among those who hatched the murder plot. So, they engaged Pandit to do the job,” said the police officer.