Menwhile, the police found explosives on the Suri-Bolpur road, a few kilometers from Banerjee's rally venue in Birbhum district.
"We have seized some explosives from under a culvert on the Suri-Bolpur Road. While the chief minister has been travelling in a chopper, the explosives were found few kilometres away from the party rally venue hours before she attended it," Birbhum's Superintendent of Police R.M. Khan told IANS.
Khan said a bomb disposal squad was immediately sent to the spot and five people have been detained in this connection.
The Election Commission said it was looking into the Trinamool complaint against it with regard to the fire.
"We have forwarded the complaint to the Commission in Delhi. They are considering it and after that they will take a decision," the state's assistant chief electoral officer Amitjyoti Bhattacharya told reporters here.
While her party leaders continued to see a conspiracy behind the incident and even attacked the poll panel, state Congress president Adhir Ranjan Chowdhury called for the intervention of the Central Bureau of Investigation.
"I think the CBI should be called in," Chowdhury said reacting to the incident.
Trinamool leader and state Sports Minister Madan Mitra said "poisonous fumes were released in the CM's room in pursuance of a conspiracy", while party general secretary Mukul Roy shot off a letter to the Election Commission crying foul over the incident.
In his letter to Chief Election Commissioner V.S. Sampath and state chief electoral officer Sunil Kumar Gupta, Roy said a "deep, devious conspiracy" could not be ruled out.
"Safety norms and procedures were completely disregarded by the administrative machinery under your control. This incident could have had fatal, disastrous consequences with repercussions in West Bengal and the entire nation. One cannot rule out a deep, devious conspiracy behind the incident," Roy said in his letter.
Police have initiated a probe into the matter and a forensic team examined the room and collected samples.
