Roy claimed that he was booked out of "political vendetta" and was in no way linked to the murder of Krishnaganj MLA Satyajit Biswas on Saturday.
Biswas (41), who represented Krishnaganj constituency in the West Bengal Assembly, was shot dead from point-blank range by unidentified assailants on Saturday evening inside a Saraswati puja marquee at Phoolbari area in the district, bordering Bangladesh.
Roy has been charged with "criminal conspiracy relating to the murder", his lawyer said.
"Roy has been implicated in about 25 criminal cases since he changed his affiliation from Trinamool Congress to BJP," Dasgupta said.
The BJP leader is one of the four persons named in the FIR relating to the killing of Biswas.
Two accused -- Kartik Mondal and Sujit Mondal -- were arrested on Sunday and have been remanded to 14 days' police custody.
Roy, a former number two in the Trinamool Congress, joined the BJP in November 2017 following differences with party supremo Mamata Banerjee.
Roy has denied the allegation of his involvement, saying the decision to name him in the FIR was "politically motivated".
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)