Subrata Mukherjee, political mentor to Mamata Banerjee and former mayor of Calcutta, died on Thursday night. He was 75.

Mukherjee, who handled panchayat and a few other portfolios in the third Mamata ministry, had been undergoing treatment at SSKM hospital.

“I have weathered many a storm in life but this one I simply cannot handle… this is one of the greatest losses of my life,” chief minister Mamata Banerjee said at SSKM shortly after Mukherjee’s death.

Minister Firhad Hakim later said: “She (Mamata) broke down… she was inconsolable. She told me that ‘on the night of the festival of lights, I never thought such darkness would descend on us’.”