The incident reportedly took place when Biswas was present at Saraswati puja at Phoolbari under Hanskhali police station area. After being shot, he was immediately taken to a local hospital where doctors announced him "brought dead".
According to the police, he was shot dead by unidentified men while he was offering prayers during Saraswati Puja celebrations at Phulbari, Jalpaiguri district, near the border with Bangladesh.
The police said he was shot multiple times from a close range when he was walking down the podium after attending the programme.
The killers fled from the area after shooting the lawmaker dead, the police said. The police are looking for the accused. A manhunt has been launched.
Biswas was with West Bengal minister Ratna Ghosh and Trinamool district president Gourishankar Dutta when he was shot dead, said reports. He recently got married
