The row over access to ₹681.12 crore in Trinamool bank accounts has reached the police, with the party’s rebel camp alleging that the funds may be ill-gotten and seeking a probe.

A group of 10 MLAs led by Biswanath Das, who won on a Trinamool ticket from
Joynagar, lodged a complaint at the Bidhannagar cyber police station on Thursday night.

Based on the complaint, the police registered an FIR and initiated a case invoking sections including cheating, criminal breach of trust, criminal conspiracy, and offences categorised as “organised crime”.

The complaint came hours after former sports minister Aroop Biswas wrote to a private bank’s south Calcutta branch, asking it to freeze the party’s accounts over apprehensions of misuse.

Leaders close to Mamata Banerjee said Aroop was no longer the party’s treasurer and had no authority to block bank accounts.

Late on Friday evening, the party’s bank accounts, holding ₹440 crore, were frozen, police said. The status of the remaining amount was not immediately clear.

The police complaint states: “It has come to my knowledge through reliable circumstances and surrounding developments that certain funds, allegedly arising out of illegal activities including misuse of influence, dishonest financial dealings, and suspected unlawful collection of money, may have been routed and subsequently deposited into bank accounts bearing numbers 50200059108xxx, 50200063079xxx, and 50200063079xxx… The pattern of such suspected financial movement gives rise to a reasonable apprehension that electronic communication systems, digital platforms, and online banking mechanisms may have been used to facilitate the transfer and possible concealment of such proceeds.”

It further states that the circumstances require “immediate and thorough investigation to ascertain the origin, movement, and destination of the said funds”.

On Friday, MLA Ritabrata Banerjee, who is leading the rebel camp, said: “Yes, 10 of our MLAs have written such a formal complaint to the cyber cell of Bidhannagar Police Commissionerate... There are well-founded apprehensions that this was ill-got wealth. Money from corruption, cut-money, extortionary activities. This should be thoroughly probed and frozen... We want the government and agencies to look into it.”

Sources in the rebel bloc said they had prepared for nearly two weeks to seize control over what they described as Trinamool’s declared funds — “at least ₹1,100 crore” by some accounts.

“We will take control of the funds. This matter may reach the Election Commission and the Supreme Court, so things may take time. These steps are being taken to ensure Mamata and Abhishek do not empty the accounts in the meantime,” a rebel MLA said.

As treasurer until June 5, Aroop had access to the accounts. Although he was replaced by former MP Subhasish Chakraborty on June 5, sources said banks and financial institutions had not yet been formally informed when Aroop wrote to the bank seeking a freeze on the accounts.