In relation to a money-laundering probe into a case of illegal coal mining, the Enforcement Directorate (ED) held TMC youth leader Vinay Mishra's brother Vikas Mishra, informed officials.
Officials added that Mishra was later produced before a special Prevention of Money Laundering Act (PMLA) court which sent him to six-day ED custody.
The central agency had filed a case under criminal sections of the PMLA after studying a CBI FIR to probe charges of money laundering in coal trading and mining.
The CBI had questioned Rujira Banerjee, wife of Abhishek Banerjee who is a Member of Parliament from Diamond Harbour constituency and nephew of Chief Minister Mamata Banerjee, in this case.
Abhishek Banerjee wields considerable influence in the party and has been leading the TMC's counter-attack in the run-up to the assembly polls.
The CBI had also questioned Abhishek Banerjee's sister-in-law in connection with the case.
It had registered an FIR in November last year against the alleged kingpin of the pilferage racket, Anup Manjhi alias Lala, ECL general managers Amit Kumar Dhar and Jayesh Chandra Rai, ECL security chief Tanmay Das, Kunustoria area security inspector Dhananjay Rai and Kajor area security in-charge Debashish Mukherjee.
According to the officials, Manjhi is allegedly involved in illegal mining and theft of coal from leasehold mines of ECL in the Kunustoria and Kajora areas.
The ED had also conducted searches against the accused in West Bengal sometime back.
Polls to the 294-member state assembly will be held in eight phases beginning March 27.
With PTI Inputs
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