New Delhi: The National Investigation Agency (NIA) has filed a supplementary charge-sheet against four people in the Khalistan Tiger Force recruitment and arms smuggling case, an official said on Saturday. The charge-sheet was filed before the Special NIA Court, New Delhi, against Amritpal Singh alias Ammy and Amrik Singh, both deported from the Philippines, and Jassa Singh and Gagandeep Singh alias Mithi, a spokesperson of the federal agency said.

Earlier, the agency had filed a charge-sheet against nine accused persons in the case on July 22.

Twelve other members of the Khalistan Tiger Force (KTF) terrorist outfit and their associates, linked with the Babbar Khalsa International (BKI) and the KTF, are under investigation for their role and involvement in this terror conspiracy.

The spokesperson said that a "listed individual terrorist", Canada-based Arshdeep Singh alias Arsh Dala, in association with accused Manpreet Singh alias Peeta, had indoctrinated and recruited Amritpal, Amrik, Jassa and Gagandeep into his terrorist group, the spokesperson said.

Operating from the Philippines, Amritpal and Amrik were actively engaged in recruiting youngsters. Their activities extended to smuggling of arms and explosives from Pakistan as well as carrying out extortion and subsequently channelizing the extortion proceeds for terrorist activities, the official said.

During the course of investigation, the NIA successfully got Amritpal and Amrik deported from the Philippines, the spokesperson said.

"The charge-sheeted accused persons played a pivotal role, at the behest of Arsh Dala, in a larger conspiracy, primarily focused on raising funds for the proscribed KTF," the spokesperson said.

The official said Arshdeep and his arrested accomplice Manpreet arranged the recruitment of potential members, forming terrorist gangs in Punjab, and carrying out targeted killings and firings at the residences of potential victims, coercing them into complying with their extortion demands.

"Investigations have also revealed that extortion funds were being systematically channelled to various foreign countries through both banking and non-banking channels. These illicit financial transactions were aimed at fuelling terrorist activities in India," the spokesperson said.

The agency said investigations have further revealed that KTF operatives based abroad were involved in regular recruitment and handling of their terror syndicate associates.

"They were also involved in smuggling of arms, ammunition, and explosives from across the border through drones etc. These terror hardware supplies were then used for carrying out terrorist activities on Indian soil," the spokesperson said.