BANGKOK - Thailand's police on Wednesday detained 100 people for their alleged involvement in a scam center in Cambodia, its first arrest of Thai nationals in a regional crackdown on massive fraud operations.

Police said those arrested were part of the criminal gang running the operation and were defrauding victims by impersonating government officials.

"These scam centers are transnational criminal organizations, being carried out by foreigners with Thais to defraud Thais," Police General Thatchai Pitaneelaboot said.

Thatchai estimated more than 1,000 Thais were still working across borders in scam centers.

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So far, about 7,000 people of more than 20 nationalities have been extracted from the scam centers, with some struggling to return home.

Most were victims of human trafficking, according to Thai authorities, who are coordinating repatriations.

Police have said Thais have since 2022 been defrauded of about 80 billion baht ($2.37 billion) in telecoms scams.

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This week, Thai Prime Minister Paetongtarn Shinawatra ordered a study on the effectiveness of building a wall on part of its border with Cambodia to prevent illegal crossings and curb illicit activities.