BANGKOK: Hundreds of thousands of people are being trafficked by criminal gangs and forced to work in scam centres and other illegal online operations that have sprung up across Southeast Asia in recent years, the United Nations said in a report on Tuesday.

The report cited "credible sources" estimating that at least 120,000 people across Myanmar and around 100,000 in Cambodia may be trapped in scam operations, with other criminal-owned enterprises in Laos, the Philippines and Thailand ranging from crypto-fraud to online gambling.

"People who are coerced into working in these scamming operations endure inhumane treatment while being forced to carry out crimes. They are victims. They are not criminals," said U.N. High Commissioner for Human Rights Volker Turk.

Cambodian police spokesperson Chhay Kim Khoeun said he had not seen the U.N. report but queried the number.

"I don't know how to respond, where did they get the (100,000) number from? Have they investigated? Where did they get the data? Foreigners are just saying things."

Myanmar's military-run government did not respond to requests for comment.

The U.N. Human Rights Office report was one of the most detailed of the phenomenon that has emerged since the COVID pandemic, fuelled by closure of casinos that prompted moves into less regulated areas in Southeast Asia.

The fast-growing scams centres are generating billions of U.S. dollars in revenue each year, the report said.

"Faced with new operational realities, criminal actors increasingly targeted migrants in vulnerable situations ... for recruitment into criminal operations, under the pretence of offering them real jobs," the report said.

It said most of the trafficking victims were from other Southeast Asian countries as well as China, Taiwan and Hong Kong, but some were recruited from as far away as Africa and Latin America.

The U.N. rights office called on regional governments to strengthen rule of law and tackle corruption to "break the cycle of impunity" that allows criminal enterprises to thrive.