The National Investigation Agency (NIA) on Wednesday filed a charge sheet against three persons for the Mysuru court blast in August last year.
The counter-terror agency accused Nainar Abbas Ali, M. Samsun Karim Raja, and S. Dawood Sulaiman of forming a terror outfit 'Base Movement' and threatening the judiciary.
The charge sheet said its investigation revealed that the bomb explosion at Mysuru courts complex on August 1, 2016, was carried out by the accused as part of a larger conspiracy.
Abbas Ali allegedly formed the 'Base Movement' outfit to further the objectives of global terror organisation Al Qaeda.
Ali also recruited four others to commit terror and anti-national activities, the agency said.
The NIA said the accused persons founded a terror outfit, sent threatening letters to various jails, senior government functionaries and the French Consulate, and carried out improvised explosive device blasts in five court premises in south India.
They allegedly also conspired to explode bombs at various places in the country.
The NIA arrested five persons after the blast occurred in a toilet of the Mysuru court complex.
The NIA said the accused persons carried out blasts in Chittoor court complex in Andhra Pradesh on April 7, 2016; Kollam courts in Kerala on June 15, 2016; Nellore court premises on September 12, 2016; and Malappuram court in Kerala on November 1, 2016.
The probe agency took up the case on September 20, 2016.