The torture and killing of the college student in Cambodia sparked a public outcry in South Korea, which dispatched a task force to the Southeast Asian nation in an effort to jointly tackle transnational cyberscam networks.

The multibillion-dollar scam industry ballooned in Cambodia in recent years, with thousands of foreign nationals involved in romance and cryptocurrency investment cons -- some willingly and others coerced by organised criminal groups, according to experts.

The court in Kampot province sentenced the six Chinese men, who ranged in age from 30 to 54, to life imprisonment on charges of murder, cruel acts and fraud via an organised group, according to a court statement.

The six were in Cambodian custody, Information Minister Neth Pheaktra said.

The South Korean student, reportedly kidnapped and tortured by a criminal gang, was found dead in a pickup truck on August 8.

An autopsy revealed he "died as a result of severe torture, with multiple bruises and injuries across his body", a court statement said.

Many South Korean victims of such crimes in Cambodia have been lured by fraudulent job offers promising high pay, Seoul has said.

In October, South Korea banned its nationals from travelling to parts of Cambodia, including the Bokor Mountain area of Kampot, after South Korea was shaken by the student's killing in Bokor city.

About 1,000 South Koreans were estimated to be working in Cambodian scam operations, targeting potential victims in South Korea, Seoul said that month.

Dozens of South Koreans who had been detained in Cambodia for their alleged links to "pig butchering" scams -- so called for the method of building trust with victims over time before stealing funds -- were repatriated at the time.