The accused, Mohit Gupta (33) is a resident of Shakarpur in East Delhi, said police.
"Gupta is an expert in computers and began to use his skills with the computer for creating fake IDs and activating SIM cards on these fake IDs and selling the same for anything between Rs 500-700," Joint Commissioner of Police (Crime) Ravindra Yadav said.
Several fake IDs, blank Customer Acquisition Forms (CAFs) were recovered from Mohit. During the screening of his personal laptop, more than 1000 fake IDs and an equal number of photographs of different persons were found in a folder, Mr Yadav said.
Mr Gupta was arrested on Friday by the inter-state cell of the Crime Branch, said police.
Gupta's name emerged during the interrogation of Ankush Khandelwal, a resident of Sector 5 in outer Delhi's Rohini locality, who also allegedly sold pre-activated SIM cards on forged IDs some of which were used by an espionage ring suspected to be backed by ISI.
Khandelwal was arrested around two weeks ago and the police recovered 205 pre-activated SIM cards and 28 forged documents from his possession.
"During investigation of the espionage case, it emerged that an Af-Pak region-based Pakistani intelligence operative was using a SIM card issued from Delhi to contact his agents in the spying ring, suspected to be backed by ISI, here.
Further investigation brought out that the SIM card was issued on forged identity proof," Yadav added.
Both Khandelwal and Gupta have been booked on the charge of cheating and forgery, police said.
On October 26, a team of Delhi Police had tracked down an alleged Pakistani intelligence operative, identified as Kafaitullah Khan while he was heading from Jammu to Bhopal, following which four persons, including a serving BSF official, a retired and a serving army personnel, were arrested.
While Khan, a native of Rajouri district in Jammu and Kashmir and alleged head of a suspected ISI-backed espionage racket, was arrested in Delhi, three others were rounded up in Rajouri and one from Siliguri in West Bengal.
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