The Enforcement Directorate has sent notices to three Trinamul Congress leaders — Firhad Hakim, Prasun Banerjee and Madan Mitra — asking them to submit the details of their bank account transactions within a week from Monday.

“We need to verify the details of the monetary transactions that happened through all the bank accounts held in their names,” said a source in the agency, which is investigating the Narada scam.

While Hakim is a minister in the state government, Banerjee represents Howrah in the Lok Sabha. Mitra is a former minister.

All these three leaders, along with other accused in the scam, had been questioned by the ED and the CBI. Their voice samples were also recorded in the course of the investigation as people resembling them were seen accepting cash in a sting operation conduced by Narada News.

“We have already asked for and received several documents from these accused persons. As the investigation proceeds, we might need more documents as well,” the source said.

A few days ago, the ED had asked BJP national vice-president Mukul Roy to share the details of his bank accounts and assets owned by him and his wife. However, this notice was in reference to the Saradha chit fund scam.

Roy, who is now recovering from a surgery, had said earlier that there was nothing to hide and he would cooperate with the investigation.

Roy — former Trinamul number 2, who joined the BJP in 2017 — is one of the accused in the Narada scam. Former Calcutta mayor Sovan Chatterjee is also an accused. Chatterjee switched from Trinamul to the BJP.