The four suspects, 42-year-old Chinese man, Chao Ji, and three Thai nationals - Salinee, 33, Jittra, 32, and Theerapat, 32, were arrested following raids across Chiang Mai, Bangkok, and Chonburi, the Central Investigation Bureau (CIB) announced on Monday.

The group is being investigated for jointly possessing devices used to illegally obtain electronic payment card data for the purpose of forging or altering card information, as reported by The Pattaya News.

According to the CIB, the network operated fruit stalls in popular tourist areas, offering Chinese tourists "exclusive discounts" if they paid with UnionPay cards. The stalls were equipped with skimming devices designed to capture customers' card information for later theft.

The bureau explained that employees were instructed to swipe customers' UnionPay cards twice. The first swipe went through a keyboard fitted with a skimming device, and the second went through a legitimate electronic data capture terminal.

When customers questioned the need for a second swipe, staff allegedly claimed it was required to apply the discount.

Investigators noted that surveillance cameras were strategically positioned to record customers entering their PINs. The stolen card data and PINs were then transmitted via the LINE messaging app to accomplices in the United States, where counterfeit cards were produced and used to withdraw stolen funds, according to the Bangkok Post.

During coordinated raids on July 22, officers searched the implicated shops and three residences linked to the suspects.

Authorities seized 11 computer keyboards modified with card-skimming devices, three EDC terminals, five computers, and 18 surveillance cameras.

Police stated that Chao admitted to his role in the operation, telling investigators that he had purchased the modified keyboards from China.