"I believe she (Banerjee) knows all these," said the legislator from Singur who has been upset since he was moved from the agriculture ministry to the low key statistics and programme implementation department last week.
The septuagenarian retired head master was Banerjee's trusted aide during the 2007 peasant movement in Singur area where a Tata Nano car plant was under construction.
The Singur movement against the Left Front's acquisition of farm land for setting up a Tata Motors Nano car plant played a key role in the Trinamool victory in last year's elections.
The minister's comments come close on the heels of the chief minister's claim that she did not need "cut money" to run her party.
"The Trinamool does not need money from the government. We will contest elections by raising money by selling my paintings," Banerjee said during an official programme Saturday.
Earlier, Bhattacharya threatened to resign from the ministry and quit politics over his ministerial transfer.
The Congress and the CPI-M are standing by him.
"What Bhattacharya said is absolutely true. Trinamool supporters are largely involved in extortion and police know it well. But they have kept mum because of pressure from cabinet members," state Congress chief Pradip Bhattacharya said.
"The chief minister is well aware her party workers are engaged in extortion," said Communist Party of India-Marxist (CPI-M) politburo member Surjya Kanta Mishra.