The arrest of three Chinese nationals in last week's crackdown on a skimmer gang suggests such gangs are no longer mainly formed of Europeans.
There are many more from China believed be using Bangkok and other important tourist districts for their criminal activities.
Having chased major skimmer gangs for a while, the Patrol and Special Operation Division (PSOD) last week tracked down the suspects as investigators learned the Chinese skimmer gang operated in much the same way as European gangs.
The suspects arrested last week were found to have allegedly stolen electronic information from ATM cards as well as debit and credit cards and sold the information to gangs overseas who used it to produce fake electronic cards for purchasing goods or withdrawing cash in other countries.
Contact Crime Track: crimetrack@bangkokpost.co.th.After being alerted to the Chinese gang by informants, PSOD chief Pol Maj Gen Surachet Hakpal ordered detectives to go undercover posing as people working near the ATMs targeted by the gang.
According to officials, the gang mounted a card reader on to the card slot of the ATMs. As unsuspecting users slip their cards into the machine to get cash, the reader copies the information from the credit card or the cash card tab.
At the same time, a small spy camera fitted by the gang captures the user keying in his or her personal identification number (PIN) to gain access to their personal account.
Detectives sent to observe the ATMs from a nearby department store on Ratchadaphisek Road reported back, saying they spotted a group of Chinese people they suspected were members of the skimmer gang which the PSOD was after.
A combined team of the PSOD and the Huai Khwang police then launched a crackdown on the gang on Tuesday when the first suspect identified as Zhong Fuhua, 31, was apprehended in front an ATM belonging to Siam Commercial Bank (SCB) located near a department store in Huai Khwang district.
Police said he was detained while retrieving a skimmer and a tiny spy camera from the ATM. Six electronic cards were also seized from the suspect.
As the police expanded their investigation, they detained two more suspects, Liu Liming, 40, and Zhu Wanrong, 47. They were arrested with their luggage as they were hailing a taxi outside an apartment, in an apparent attempt to flee.
Another suspect, identified as Zhong Lang Ming, is still on the run.
According to Pol Maj Gen Surachet, Zhong Fuhua allegedly admitted to working for the gang.
He said his job was to collect the skimmers and tiny spy cameras fitted to the ATMs by the gang.
Zhong Fuhua told investigators he was involved in the information theft.
He said he was staying with Mr Zhu at a rented apartment they shared with Mr Liu, and that he was introduced to the gang by Zhong Lang Ming.
Mr Liu, meanwhile, told police that Mr Ming is the gang leader who installs the skimmers and the tiny cameras on the ATMs. Mr Zhu, however, denied any wrongdoing.
The police said evidence suggested the skimmer gang came from the southeast Chinese province of Jiangxi. The gang members made three or four previous visits to Thailand.
Each time, they took precautions to avoid police attention.
The information police obtained about the gang corresponds with the seizure of air tickets to Shenzhen, in southeastern China, which the arrested suspects said they had prepared for escaping from Thailand.
And as police delved into the gang's criminal history, they found information suggesting the gang may also be responsible for several previous information cases of theft not only in Bangkok but also Chiang Mai and other major provinces.
Pongsit Chaichutpornsuk, first executive vice-president of the SCB who oversees the bank's prevention of financial crime, said Thailand is under heavy attack from skimmer gangs and is now ranked sixth worst in the world for this practice.
However, he said the Zhong Lang Ming-led gang was busted before it could steal money using fake credit cards.
Once most of the gang members were arrested, police found they had skimmed enough information to produce more than 200 fake electronic cards per day, which can cost a bank more than 10 million baht in losses, he said.
The SCB has vowed to closely monitor skimming gangs and watch out for any signs of unusual transactions among its customers. When suspicious transactions are detected, they will be suspended immediately and inspected, he said.
Mr Pongsit warned electronic card users to be wary of information theft as thieves can strike when they are not watching.