Police from Thailand’s Cybercrime Investigation Bureau arrested two men, believed to be members of a call centre scam gang, and seized 38 SIM boxes (SIM-Banks) in raids on 11 apartments in the southern province of Chumphon yesterday (Tuesday).
Cybercrime Investigation Bureau Commissioner, Pol Lt-Gen Worawat Watnakhonbancha, said that each SIM box can handle 32 SIM cards at the same time and the 38 SIM boxes seized can handle up to 600,000 telephone calls a day.
The SIM boxes are believed to be have been smuggled into the country from Cambodia, via a border crossing in Aranyaprathet district of Sa Kaeo province.
The use of SIM boxes is the most common tool for interconnect bypass fraud by call centre fraudsters. When the fraudsters intercept the call, they route it using VOIP to make it seem like it is a local call and then pocket the fee that the local network operator should have received.
A senior police officer said that the SIM boxes have to be used in connection with the internet and the boxes must not be placed close together, otherwise their signals will interfere with each other, so they were scattered over 11 rented rooms.
Cybercrime Investigation Bureau officers launched the investigation after a mobile phone service provider reported an unusually high amount of international phone traffic in Chumphon province.
An official of Advanced Info Service (AIS) said that an individual can import the SIM boxes if they have permission and the boxes are usually used in businesses, which frequently make international phone calls to, save cost.
He said that the illegal call centre had, however, modified the devices to dupe mobile phone users by claiming to be tax officials or post office employees.
The two suspects were charged with possession of telecommunication devices without permission, which is subject to imprisonment of not more than five years and/or a maximum fine of 500,000 baht on conviction.