The earliest public warnings about the reckless and fradulent CIS in West Bengal started in 2009 from MPs Somendra Nath Mitra and Abu Hasem Khan Choudhury and TMC leader Sadhan Pande [REF].
On 6 April 2013, Sen wrote an 18-page confessional letter to the CBI, in which he admitted that he had paid large sums of money to several politicians [REF].