Builder -Bank Collusion Home Buyers In Serious Condition

I recently file A FIR 420 against Builder .Builder has taken so many loan from the different bank which is now became under NPA Bank builder mixed collusion Bank has also offered doubled finance on single flat , loan on bank already mortage flat and many other things .bank officals are mixed with in neither they are taking action against builder coz if they will investigate there job will be in danger they just spending time to avoid the problem tht will arise in Future . I want to Destroyed the whole Scam as he taken bad loan as well as fraud with buyers with bank collusion . What will be the process of getting the detail documents of the proof from the bank of his bad loan ,how much loan did he taken and what secruity he given to bank of bad loan and why bank not taken action against his employes ?