NEW DELHI: TMC leader Koel Mallick on Thursday resigned from the Rajya Sabha amid the ongoing exodus of MPs and MLAs from the Mamata Banerjee-led party, news agency ANI reported, citing sources.“Rajya Sabha MP from TMC, Koel Mallick met Vice President and Rajya Sabha Chairman CP Radhakrishnan and has submitted her resignation,” sources told ANI.The resignation came a day after TMC MLA and Mamata Banerjee’s close aide, Madan Mitra, quit the party and joined the rebel TMC faction headed by Ritabrata Banerjee.Earlier, Sukhendu Sekhar Ray, Sushmita Dev and Prakash Chik Baraik resigned from both the Rajya Sabha and the TMC before joining Bharatiya Janata Party .They also filed their nomination papers on Monday for the Rajya Sabha bypolls in West Bengal, with the BJP defending its decision to field the former TMC leaders despite its earlier pledge not to induct leaders from the Trinamool Congress.