The multibillion-dollar scam industry has ballooned in Cambodia in recent years, with thousands involved -- some willingly and others forced by organised criminal groups, experts say.

Cambodia's anti-cybercrime commission said in a statement that local authorities raided a building where scam operations were suspected in the capital Phnom Penh on Wednesday.

Police arrested 57 South Koreans and 29 Chinese nationals during the operation, the commission said.

Authorities also seized 126 computers and 30 phones, it added.

But South Korea's foreign ministry later Thursday denied there were fresh arrests, telling AFP in a statement that the 57 South Koreans were apprehended by Cambodian authorities in July, and many of them were repatriated on October 18.

A representative of the Cambodian commission could not be reached late Thursday for clarification.

Over the weekend, Cambodia sent home 64 South Korean nationals who had been held for their alleged links to "pig butchering" scams -- so-called for the method of building trust with victims over time before stealing funds.

The high-profile repatriations follow public outcry over the torture and killing of a South Korean college student in Cambodia this year, reportedly by a crime ring.

Last week, South Korean foreign ministry officials met with Cambodia's prime minister and local police to discuss fake job and scam centres.

South Korean Foreign Minister Cho Hyun said Monday that 10 more alleged scammers were arrested and two individuals were rescued.

About 550 South Koreans were reported missing or held against their will after entering Cambodia since last year, the foreign ministry said this month.

Seoul estimates around 1,000 South Koreans are among approximately 200,000 people working in scam operations in Cambodia.

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