SIM-card cyber fraud racket under CBI scanner

The Bihar Police initially probed the case, which the CBI recently took over due to the involvement of accused from other states

Mumbai: The Central Bureau of Investigation (CBI) has launched a probe into a cyber-fraud network that allegedly used bulk, fraudulently obtained SIM cards to target thousands of individuals across the country. The Bihar Police initially probed the case, which the CBI recently took over due to the involvement of accused from other states.

SIM-card cyber fraud racket under CBI scanner

According to CBI, the network employed a sophisticated setup involving SIM boxes to convert Voice-over Internet Protocol (VoIP) calls into local calls, thereby masking their origin and bypassing security checks. Using this method, the accused allegedly made over 15,000 calls across India within a fortnight between June and July 2025 from a base in Bihar’s Supaul district.

A SIM box routes international calls through local SIM cards, making them appear domestic, while VoIP technology enables voice communication over the internet instead of conventional phone lines. Investigators said this modus operandi is commonly used in call-based frauds to conceal the source of operations.

The CBI recently took over the case from the Bihar Police, citing its inter-state ramifications, and registered an FIR on March 18 under relevant provisions of the Bharatiya Nyaya Sanhita, the Telecommunication Act, and the Information Technology Act. The case originated from a complaint filed by a Bihar Police officer following an alert from the Department of Telecommunications’ Digital Intelligence Unit.

According to investigators, the accused formed an organised network to illegally procure SIM cards, operate SIM boxes, and route VoIP calls locally, resulting in financial fraud and revenue losses to telecom operators and the government.

“A secret investigation and technical analysis was conducted to determine where and by whom the said illegal SIM box was being operated in Supaul district. The investigation revealed that the SIM box was owned by Harshit,” a CBI official said.

Harshit was arrested by the Bihar police in July 2025. A search conducted at his house allegedly led to the recovery of the black–coloured rectangular SIM box, around 800 SIM cards and various documents including a purported notice from Maharashtra’s Nagpur (rural police), according to CBI.

Investigators suspect that the SIM cards were procured using forged biometric and facial recognition data. The CBI said the probe is at an initial stage and efforts are underway to identify the masterminds, their associates, and mule account holders involved in the wider cyber-fraud network.