Delhi Police on Wednesday filed a chargesheet before a city court under the stringent law Unlawful Activities (Prevention) Act (UAPA) and other sections against 15 persons for larger conspiracy in the North-East Delhi riots case that occurred in February. Special cell of the Delhi Police told the court that it has relied upon CD-R and Whatsapp chats. In its chargesheet running into 17,000 pages, the police has listed 747 witnesses and of them 51 have recorded their statements before the magistrate under CRPC 164.