Kolkata: Kolkata Cyber Police arrested three persons who duped a senior citizen of Rs 3 crore through digital arrest fraud and seized six SIM boxes and 130 active SIM cards, which were all embedded in a wired system that resembled a grocery store. Arpan Sikdar, 24, a resident of Maniktala was arrested on Wednesday. Two others were arrested earlier.Investigators said the complainant, Bidhan Ghosh Dastidar, was contacted around Oct 5 last year by persons who posed as officials of courier services and told him that a parcel in his name contained illegal articles. Using the usual modus operandi, the callers then claimed that the matter was under investigation by the CBI and the Enforcement Directorate. One caller, posing as a CBI officer, showed forged identity cards and threatened arrest on a video call. The complainant and his wife were then forced to remain on video surveillance. Officers said other persons joined later, posed as senior officials and sent forged documents carrying the logos of the CBI, RBI, ED and the Supreme Court of India. Under threat, Dastidar transferred Rs 3 crore to bank accounts used by the accused, police said. During probe, police examined the calling numbers used to contact the complainant and traced them to an ‘illegal SIM box setup’ in north Kolkata. In that operation, officers seized 12 SIM boxes and 2,000 SIM cards and arrested two persons.Joint CP (crime and traffic) Rupesh Kumar said a laptop seized in that raid was later sent for forensic imaging, data extraction and artefact analysis. Examination of browser history and network logs showed access to web-based control panel IPs, linked to a platform used as a command-and-control panel. Investigators said the panel enabled remote configuration and operation of illegal SIM box infrastructure, including VoIP routing, call masking and traffic manipulation.A reverse IP lookup and Internet Protocol Detail Record analysis then showed repeated authenticated sessions from a broadband subscriber identified through KYC records as Mili Mondal of Ashoknagar in North 24 Parganas, police said. Based on that lead, a raid was conducted at the premises linked to the subscriber.Officers said the search did not at first locate the router or SIM boxes. Mili, her parents and her boyfriend Arpan Sikdar were questioned. Police then carried out technical verification with a Wi-Fi scanning application and detected multiple wireless access points with similar names within the premises. Using range narrowing, the team identified the location of concealed network devices.The search led to the recovery of a SIM box setup hidden inside cardboard boxes with power and router connections, police said. The devices had been covered with jute bags and garbage. Items seized from the spot included six SIM boxes in working condition, 130 active SIM cards inserted in the devices, three mobile phones, four routers and other accessories.
