Trinamool Congress leader Dinesh Trivedi announced his resignation in parliament today, adding to a series of dramatic exits from Mamata Banerjee's party ahead of the Bengal election due by May. He said he felt helpless about the political violence in his state. "The kind of violence that is happening in Bengal, it is a threat to democracy. I feel very strange sitting here. I think of what I should do. I think of Rabindranath Tagore. Obey party discipline? Of course, but I feel stifled. My soul is saying I sit here and say nothing, what is the point? I resign," Mr Trivedi said in the Rajya Sabha.