Delhi Police has busted a cross-border cyber fraud network and arrested three people operating from Uttar Pradesh and Haryana, officials said on Tuesday.
The accused were involved in large-scale digital arrest and investment frauds in collaboration with cyber criminals based in Cambodia, Thailand, Canada, and other countries, police said.
As part of the crackdown, police also dismantled Session Initiation Protocol (SIP) numbers and terminals used to route fraudulent calls, officials added.
Deputy Commissioner of Police (DCP) (Outer North) Nidhin Valsan said the breakthrough came after a complaint was filed on the National Cyber Crime Reporting Portal (NCRP) regarding a financial fraud of Rs 94,000.
The complainant received a call on December 19, 2024 from a number impersonating officials from the Central Bureau of Investigation (CBI) and the Telecom Regulatory Authority of India (TRAI), the officer said.
The scammers falsely claimed that her mobile number was being misused for illegal activities and threatened her with arrest unless she made payments. Fearing consequences, she transferred the money via UPI to accounts under different names, he said.
Following the complaint, an FIR was registered under relevant sections of the Bharatiya Nyaya Sanhita (BNS) at the Cyber police station of Outer North district and an investigation was launched.
Using money trails, and call detail records, police traced the cyber criminals and their SIP trunking operations, leading to the arrest of -- Ajaydeep (32), Abhishek Srivastava (34) and Ashutosh Bora (30), -- the DCP said.
Ajaydeep, a B.Tech and MBA graduate, who formerly worked for an NGO, had rented an office in Lucknow for SIP trunk calls services, while Abhishek, trained in computer and CCTV hardware repair, assisted in setting up SIP-based infrastructure, police said.
Ashutosh, a law student from Gurugram was the key facilitator for international cyber criminals. He facilitated SIP services for cyber criminals operating in Cambodia, Thailand, and Canada and was directly linked to international cyber gangs, they added.
The officer said that Ajaydeep and Abhishek were arrested on January 29, from Lucknow and Mirzapur in Uttar Pradesh, while Ashutosh was apprehended on February 2.
Explaining about the SIP technology, the DCP said that "SIP service provider" is a company that lets someone make phone calls over the internet using their existing phone system, essentially providing a way to connect their office phones to the internet instead of traditional phone lines.
The SIP acts like a bridge between the phone system and the internet, allowing someone to make calls through a computer or special phone devices, and often offers features like call forwarding and voicemail, similar to a regular phone service, but online, he said.
The officer said the modus operandi of the scam was executed through SIP trunking, a technology used for Voice over Internet Protocol (VoIP) calls. The accused exploited SIP services to facilitate illegal call terminations, which made it seem like the calls were from legitimate Indian landline numbers.
He said that the accused posed as officials from CBI, TRAI, or DoT and falsely accused people of crimes and threatened them with arrest. The victims were then coerced into transferring money via UPI transactions to mule accounts, to avoid "arrest".
The scammers used autodialers and cloud PBX soft switches to manage thousands of calls. SIP trunks allowed them to bypass call monitoring at international gateways, making it difficult to trace their origin, the officer added.
Multiple devices, including routers and media gateways, were used to handle large-scale operations. The police team recovered hi-tech laptops, desktop computers, routers, SIP trunking media gateway, hi-tech mobile phones, fake rent agreements, the DCP said.
During interrogation the accused revealed their connection with Mohammad Ali, an Indore-based mastermind behind the digital arrest scam. Ali is suspected to be coordinating fraud modules across multiple countries, he said.