[4] The primary mandate of the agency is to investigate and prosecute offences that have national and cross-border implications, specifically focusing on terrorism, insurgency, and other related matters.

It has the authority to conduct searches, make seizures and arrests, as well as to collect evidence and maintain a database of terrorist organisations and their members.

[5][7][8][9] Headquartered in New Delhi, the NIA has branches in Hyderabad, Guwahati, Kochi, Lucknow, Mumbai, Kolkata, Raipur, Jammu, Chandigarh, Ranchi, Chennai and Imphal.

There are branch offices across the country to ensure nationwide coverage and coordination in counter-terrorism and other national security-related investigations.

[11] Officer Ranks in the NIA includes DGs, ADGs, IGs, DIGs, SPs, Add.SPs and DSPs.

As per the legislation, NIA has concurrent jurisdiction which empowers the Central Agency to probe terror attacks in any part of the country, covering offences including challenges to the country's sovereignty and integrity, bomb blasts, hijacking of aircraft and ships and attacks on nuclear installations.

[15] The amended legislation, which aims to primarily empower the anti-terror agency to investigate scheduled offences such as human trafficking; circulation of fake currency; manufacture and sale of prohibited arms; and cyber-terrorism, was passed with a majority of 278 votes in favour and six against in the Lok Sabha.

[19] In 2016, Home Minister Rajnath Singh wanted to end the central agency's dependence on approval from state police chiefs before confiscating or attaching assets of people accused of crime.

These are presided over by a judge appointed by the Central Government on the recommendation of the Chief Justice of the High Court with jurisdiction in that region.

[25][26] This chargesheet was filed after nearly eight months of investigations spanning six states in India during which over 300 witnesses were examined, 950 "incriminating documents" and 600 electronic devices were seized.

[28] During the investigation the NIA has arrested people allegedly involved in stone-pelting incidents for the first time including Kashmiri photojournalist Kamran Yusuf.

[29][30][31] It has identified two Naxalite commanders in Bastar who were part of the ambush that killed almost the entire Congress' Chhattisgarh top brass.

[38] A US Embassy cable accessed by The Hindu says that union home minister P Chidambaram, in his discussion with FBI Director Robert Mueller, was coming 'perilously close to crossing constitutional limits' in empowering the NIA,[39] and also that the National Investigation Agency's powers could be challenged in the courts as violating constitutional provisions on Centre-State relations.