The multi-crore Saradha ponzi scam has now come knocking at West Bengal Chief Minister Mamata Banerjee's door. It now appears that, back in 2010, when Ms Banerjee was the Union Railway minister, the Saradha Group had bagged a contract with the Indian Railway Catering and Tourism Corporation, or IRCTC. It puts out of court her claims that she was not too familiar with the group till it went bust in 2013.