A Trinamool Congress party office was set ablaze on the party's 18th foundation day today at Uluberia in the district.
Police, who rushed to the spot, said the early morning blaze also gutted several adjoining shops.
Inquiry into the blaze is on, the police said.
TMC MLA Nirmal Majhi has alleged that BJP and CPI-M were behind the blaze.
Majhi said photos of Chief Minister Mamata Banerjee and Uluberia MP Sultan Ahmed, which were kept in the office for the day's programmes were reduced to ashes.
Both parties when contacted, denied the charge.
