NIA said that Siddiqui was actively involved in radicalisation on behalf of the ISIS from India.
A "highly radicalised" operative of the ISIS 'Voice of Hind' module was arrested as the National Investigation Agency raided two locations in Uttar Pradesh and Delhi on Wednesday, an official said.
Basit Kalam Siddiqui (24), a resident of Varanasi in Uttar Pradesh, was arrested in a case related to a conspiracy by the proscribed terrorist organisation Islamic State of Iraq and Syria (ISIS) to radicalise and recruit youngsters to wage violent jihad against the Indian State by carrying out acts of terrorist violence, a spokesperson of the federal agency said.
The National Investigation Agency (NIA) had registered the case suo motu on June 29 last year under various sections of the Indian Penal Code and the Unlawful Activities (Prevention) Act.
"Siddiqui was in active touch with ISIS operational handlers and was indulging in content creation, publication and dissemination of ISIS propaganda through a magazine 'Voice of Khurasan'," the official said.
"On the directions of his ISIS handlers based in Afghanistan, he was trying to fabricate an explosive 'black powder' and gain knowledge on the use of other lethal chemical substances to be used for the fabrication of improvised explosive devices (IEDs)," the NIA spokesperson said.
The NIA said he was also imparting training on making of explosives through several Telegram groups operated by him and for carrying out terrorist attacks against vital installations and the civilian population.
"He was also preparing to undertake 'hijrat' (migration) to Khorasan (Afghanistan) for joining active ISIS terrorists in combat," the spokesperson said.
During its searches, the NIA seized incriminating articles such as handwritten notes related to making of IEDs and explosive substances, mobile phones, laptops and pen-drives, the official said.
The spokesperson said that during investigation, it was found that Siddiqui was actively involved in radicalisation and recruitment of radicalised youth on behalf of the ISIS from India.
After busting of the 'Voice of Hind' module by the NIA and arrest of six people, including its so-called 'amir' (chief) of Islamic State Jammu and Kashmir Umar Nisar alias 'Qasim Khurasani', through a revised strategy, online propaganda was being pushed through a new online magazine 'Voice of Khorasan'.
The NIA had earlier filed a main charge sheet and a supplementary charge sheet in the NIA Special Court in Delhi in the case against the six arrested persons.
While the supplementary charge sheet against Afshan Parvaiz Jarabi and Tawheed Latief Sofi, both residents of Srinagar in Jammu and Kashmir, was filed on March 11, a charge sheet was earlier filed against four ISIS terrorists, including Nisar, in January.
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