Korean Police Bust International Voice Phishing Ring Using Spoofed Domestic Numbers; 17 Arrested

Daegu Police arrested 17 members of an international voice phishing ring that used illegal relay devices to disguise overseas calls as domestic Korean numbers (010 format). The gang, operating since May, caused confirmed damages of approximately 340 million won by tricking victims into believing fraudulent calls came from legitimate financial institutions or government agencies.

Overview of the Case

Daegu Police arrested 17 individuals, including ringleader A (male, 20s), for operating illegal relay devices that spoofed overseas phone numbers as domestic Korean "010" numbers. The suspects were charged with violations of the Telecommunications Business Act and facilitating communication fraud losses. Seven were prosecuted.

How the Scam Worked

Under instructions from overseas-based voice phishing criminal organizations, the suspects installed and operated caller ID spoofing relay devices in villas and lodgings in Daegu starting in May 2024.

The Technical Method:

Incoming calls from overseas were relayed through illegal devices
Calls appeared to originate from domestic "010" numbers on recipients' phones
Victims believed they were receiving legitimate calls from banks or government agencies
The spoofed numbers appeared identical to real institutional contact numbers

Police shut down 13 locations and seized approximately 3,500 items including routers, mobile phones, SIM cards, and laptops.

Confirmed Damages

Identified fraud losses totaled approximately 340 million won. Device managers were paid 200,000 to 300,000 won per day.

Warning Signs and Prevention

Red Flags:

Unsolicited calls claiming to be from banks, tax offices, or police
Requests for personal information under the guise of verification
Pressure to act immediately (frozen accounts, unpaid taxes, etc.)
Unusual phone formatting or poor call quality

Protection Steps:

For calls claiming to be from financial institutions, hang up and independently call the official number to verify
Never share account numbers, OTP codes, or other sensitive personal information
Reject suspicious calls and consult with trusted third parties
Do not sell or transfer mobile phones or SIM cards to others (may constitute criminal facilitation)

Emerging Trends in Phishing Technology

While "SIM boxes" dominated previously, criminals now increasingly use iPhones as relay devices. Additionally, foreign nationals residing in Korea are being recruited as operators to install devices in hotels and other lodgings.

Where to Report

Phishing Suspicions: 112 (Police) / 1377 (Information and Communications Promotion Agency)
Financial Fraud: Financial Supervisory Service