National Investigation Agency (NIA):
The National Investigation Agency (NIA) is a central counter-terrorism agency functioning under the Ministry of Home Affairs, Government of India. The National Investigate Agency was created by an Act of the Parliament of India in 2008. It was created after the Mumbai Terror Attack with the provisions for taking up particular cases under particular Acts for investigation and prosecution.
Central Bureau of Investigation (CBI):
The Central Bureau of Investigation (CBI) is the principal investigative police agency in India. It is occupied in the compilation of criminal intelligence pertaining to three of its main areas of operation- Anti-Corruption, Economic Crimes, and Special Crimes.