A group of 64 South Koreans detained in Cambodia for alleged involvement in online s2cam operations arrived in Seoul on Saturday, with most expected to face criminal investigations, according to South Korean authorities.

The repatriation comes in the wake of public outrage over the reported murder of a South Korean college student in Cambodia in August. The student was allegedly tortured and killed in a case tied to a fraudulent employment scheme.

Several returnees, some wearing masks and caps, were seen arriving at Incheon International Airport under police escort. Their hands appeared to be cuffed, though concealed under cloth.

Read more: Freed scam compound workers recount horrific abuse: The Guardian

Torture case sparks crackdown on scam compounds

Second Vice Foreign Minister Kim Jina, speaking at the airport, said the operation confirmed “the Cambodian government’s continued crackdown” on scam-related networks and demonstrated “close cooperation” with Seoul.

“Our government will build and actively use an effective system to eradicate scams targeting South Koreans in Cambodia,” she added.

The recent murder case heightened scrutiny of the voice-phishing networks operating out of Southeast Asia, where foreign nationals, including South Koreans, are often lured by fake job offers and then forced into cybercrime.

Cambodia, South Korea boost cooperation on cybercrime

A senior police official confirmed that Cambodian authorities had agreed to alert Seoul of any arrests involving South Korean nationals and to facilitate their return to face prosecution under South Korean law.

Authorities in Seoul said investigations would now focus on exposing the organizational structure, scale, and networks behind these operations.

According to the United Nations, scam centers across Southeast Asia have proliferated since the COVID-19 pandemic, generating billions of dollars annually for transnational criminal networks.

Seoul targets voice-phishing networks and recruitment schemes

Earlier this week, South Korea issued a "code-black" travel advisory for certain regions of Cambodia and dispatched a team of senior officials to assist citizens trapped in scam compounds.

South Korea’s National Security Advisor Wi Sung-lac revealed that more than 1,000 South Koreans are believed to be among some 200,000 foreign nationals working under coercion in such compounds across Cambodia.

President Lee Jae Myung has ordered immediate action to remove illegal job postings online, not only for Cambodia but across Southeast Asia.