Kolkata, Aug 30 (PTI) The Enforcement Directorate on Tuesday issued a summons to Trinamool Congress" national general secretary Abhishek Banerjee for questioning in connection with its probe into the ‘coal pilferage scam’, an official said.The central agency asked Banerjee, the nephew of West Bengal Chief Minister Mamata Banerjee, to appear at its Kolkata office on Friday morning, he said."We have summoned Abhishek Banerjee to appear before our sleuths here. Our officers from New Delhi will come to interrogate him," the senior ED officer told PTI.While attacking the BJP during a programme, TMC supremo Mamata Banerjee had on Monday apprehended that the central agencies might send notices to her nephew, considered the second in command in the party, and other senior leaders. PTI SCH BDC BDC