South Korean police said Tuesday they have arrested 41 people in China for alleged telephone-based financial scams in rare cooperation with their Chinese counterparts.

The Seoul Metropolitan Police Agency said they arrested 39 South Koreans and two ethnic Koreans in China for allegedly opening call centers in China and making random calls to South Korean citizens, fooling them by offering to grant loans or protect their deposits.

After dividing their roles into team leaders and counselors, the suspects prepared 87 different scam scenarios to adapt to each recipient's situation, police said.

In most of the cases, they took money from those who had debt by offering loans at a lower interest rate than those they were currently paying, but the victims would first need to pay off the original loan. Then, the scammers would transfer the victim to another group member pretending to be the original lender and steal the money sent to pay off the original loan. Victims would sometimes borrow money from people around them to pay off the original loans. 

The scammers even disguised themselves as a wine sellers and an electronics store.

Some 2.14 billion won ($1.84 million) in total from 423 victims was siphoned off by the swindlers between October 2012 and June 2015.

The rare cooperation between South Korean and Chinese police came after a senior South Korean police officer visited China in May to seek a joint probe on telephone-based financial scams.

South Korean and Chinese police arrested five suspects by raiding their call center in China's eastern city of Qingdao on June 19, according to the South Korean police.

The arrest came about three months after obtaining details on the call center and its members from six others, who were detained for allegedly withdrawing money or providing bank accounts for the scammers.

Police said they later arrested 30 other scammers when they came to South Korea.

"Local authorities' support is crucial to arrest the leaders of the phone-based scam groups as they often stay abroad," said a spokesman for the SMPA, adding they are expecting further collaboration.

A total of 35,859 voice phishing cases occurred in 2014, compared with 22,351 recorded in 2012, according to the Supreme Prosecutors' Office. (Yonhap)