Mamata Banerjee has created an unprecedented political controversy - her party today vowed to fight the nominal hike in train ticket fares announced, a decision made by its own minister Dinesh Trivedi. Not only is Mr Trivedi a senior leader from Ms Banerjee's party, the Trinamool Congress (TMC), but he is also her nominee to the union cabinet. The TMC has publicly attacked its own man; it has also left the government reeling with embarrassment.