Bengal Chief Minister Mamata Banerjee lashed out at Prime Minister Narendra Modi and the BJP and sat on a dharna to "Save the Constitution" this evening after a huge showdown between the police and officials of the Central Bureau of Investigation. The CBI wanted to quiz Kolkata police chief Rajeev Kumar in two Ponzi schemes, over which several leaders of the Ms Banerjee's party have been arrested. Five CBI officials, who turned up at Mr Kumar's home, were taken to a local police station and allegedly detained. "How dare you come to a police commissioner's home without a warrant," Ms Banerjee furiously demanded, accusing the BJP-led central government of trampling over people's constitutional rights.