Prime Minister Narendra Modi addressing a rally in West Bengal's Madarihat on Thursday, April 7, 2016.

Highlights Today bridge collapsed, tomorrow Bengal will: PM takes on Mamata Banerjee

TMC stands for terror, maut (death) and corruption, says PM

What PM said was unbecoming of his high office: TMC's Derek O'Brien

What PM said was unbecoming of his high office, more like a Shakha Pramukh. My statement on FB LIVE #BengalPolls >> https://t.co/PzHHS6RUAF - Derek O'Brien (@quizderek) April 7, 2016

Prime Minister Narendra Modi today said the Kolkata flyover tragedy, in which 26 people were killed last week, was "God's message to people to save Bengal from the Trinamool Congress". Chief Minister Mamata Banerjee, he said, was "shamelessly" playing politics over the deaths.Addressing an election rally at Madarihat in north Bengal, the Prime Minister said normally, when such a tragedy takes place and a chief minister goes to the spot, "they try to save people, assist in rescue work".But the "first thing she (Ms Banerjee) did was to declare that it was the Left Front that gave the contract (for the project),... for Didi, it's the chair which is only visible and not the dying people," he added.The bridge collapse, he said was an act of god in the sense that "it happened during election time, so people may know what kind of government she has been running"."God has sent a message to the people -- that today this bridge has collapsed, tomorrow she will finish off entire Bengal," he said.In Asansol, PM Modi made a jab at the Ms Banerjee's party, the Trinamool Congress, asking his audience what the letters TMC stood for. "T for Terror, M for Maut, C for corruption," he said.Later, Trinamool Congress lawmaker Derek O'Brien hit back at the PM, tweeting:In a Facebook live post addressing PM Modi, Mr O'Brien denied the charges and said it does not befit a Prime Minister to use such words. "We expect you now to grow with your job."With Assembly elections underway in Bengal, in which the BJP hopes to increase its footprint, the collapse of the flyover on March 31 has become a huge political controversy.The Trinamool has claimed though the collapse happened on their watch, the contract was awarded by the previous Left Front government. The Left and the BJP have alleged that the government had continued with the same builder, the IVRCL, despite it being blacklisted by some states.