Gobindo Adhikari, his wife Namita Adhikari and their son Gourab Adhikari were critically injured in the attack and rushed to state-run MR Bangur Hospital, from where they were shifted to the S. S. K. M Medical College & Hospital.

Gobindo Adhikari, an active BJP worker in the area, was the party's polling agent in the recently concluded Lok Sabha elections.

Three people -- Archan Bhattacharya, Subhash Debnath and Sumit Debnath -- have been arrested in this connection.

A political slugfest has already erupted in the area over the incident.

"Those who have attacked Gobindo, his wife, and his son are active Trinamool Congress workers. BJP was leading from the polling booth where Gobindo was the polling agent in the recently concluded Lok Sabha elections. He was also threatened then by the goons backed by the ruling party," said local BJP leader Debnath Chakraborty.

However, local Trinamool Congress councilor Rajib Purohit denied the involvement of his party workers behind the event and said that it happened due to an old rivalry between the two families.

Investigation is on.