Strange Signal... Chinese Installing Modified '070→010' Relay Device in Hotel

Strict Ban on Using Such Devices under the Telecommunications Business Act
Crime Committed at Two Hotels in Jeju-si from the 6th to 8th of Last Month

An illegal Chinese resident was caught installing 'caller ID spoofing relay devices,' primarily used in voice phishing, at two hotels in Jeju City.

On the 12th, the Jeju Western Police Station announced that they have arrested and are investigating a Chinese illegal resident, Mr. A (male, in his 20s), on charges of violating the Telecommunications Business Act and Immigration Control Act.

Mr. A is suspected of installing and operating unregistered 'caller ID spoofing relay devices' at two hotels in Yeondong, Jeju City, between the 6th and 8th of last month.

At the beginning of last month, the police obtained information from a telecommunications company and searched hotel areas in Jeju City. On the 8th and 9th of last month, they discovered and collected modified relay devices at two hotels in Jeju City. However, Mr. A had already fled by then.
[Photo by Jeju Police Agency]

The caller ID spoofing relay device is a device that changes overseas caller phone numbers starting with '070' to domestic general mobile phone numbers such as '010.' Due to its nature, it is often used by telephone financial fraud (voice phishing) organizations.

The Telecommunications Business Act strictly prohibits the use of such devices.

After obtaining information from a telecommunications company in early last month, the police searched the hotel area in Jeju City and discovered and confiscated the spoofing relay devices at two hotels on the 8th and 9th of last month. However, Mr. A had already fled by then.

The police tracked Mr. A's whereabouts and arrested him on the 4th at a house in Jeju City.

During the police investigation, Mr. A reportedly stated, "I just received the relay device someone threw into the trash and installed it."

A police official said, "Through tracking, we were able to find the spoofing relay device within 3 to 4 days of Mr. A turning it on and operating it," adding, "Fortunately, there have been no reports of calls made through the relay device or related damages."

The police are investigating additional offenses related to Mr. A and plan to send the case to the prosecution.

Crimes Committed by Installing Spoofing Relay Devices on Uninhabited Islands

On the 28th of last month, a group installing voice phishing relay devices that convert internet phone numbers to domestic mobile phone numbers on an uninhabited island in the Nakdong River was arrested in large numbers. This is the first case of being caught installing voice phishing relay devices on an uninhabited island in South Korea.
[Photo by Busan Police Agency]

On the 28th of last month, a group was arrested en masse for installing voice phishing spoofing relay devices that convert internet phone numbers to domestic mobile phone numbers on an uninhabited island in the Nakdong River. This is the first case of voice phishing relay devices being installed on an uninhabited island in South Korea.

According to the Busan Police Agency, the group operated six organizations in China from July 2018 to last September to carry out voice phishing crimes.

When calls were made to the internet phone number '070,' the relay devices installed domestically converted the number to '010' before making impersonation calls to victims.

The impersonation calls varied, including pretending to be prosecutors, financial institutions, or children. They threatened victims by claiming involvement in crimes through calls impersonating prosecutors or deceived them by pretending to be their children asking for mobile phone screen repair fees.

Notably, the group installed relay devices even on uninhabited islands at the Nakdong River estuary to evade crackdowns. They recruited two Korean fishermen in their 70s who operated in the area to monitor anyone entering the islands, and remotely cut off the relay device's power whenever the police entered the islands.

The police conducted search operations about ten times over approximately one and a half years using maritime police vessels, even staying overnight on the islands, but repeatedly failed to find the relay devices due to the fishermen's alternating surveillance.

Eventually, the police succeeded in discovering a relay device hidden in the central reed field of Sinjado Island after entering the island on a jet ski.

The relay device was concealed under a small tent installed in the reed field and was powered by solar panels.

A police official said, "Since entering the island by boat could lead to being tracked, we pretended to be lost and entered on a jet ski to find the relay device," adding, "The two fishermen conducted thorough alternating surveillance, and it appears the group knew the police stayed overnight on the uninhabited island."

Police investigations revealed that the relay device installed on the uninhabited island could make up to 200 calls at once. The batteries and solar panels required for the relay device were purchased directly by the fishermen.

The Busan Police Agency's Violent Crime Investigation Unit arrested three voice phishing call center members and 20 people who operated and managed the spoofing relay stations on charges including organizing a criminal group and fraud under the Criminal Act. Among them, 16 were detained. The two fishermen who installed the relay devices were also detained.

This content was produced with the assistance of AI translation services.