In one of the largest crackdowns in recent Cambodian history, police arrested 121 Chinese nationals on Tuesday following raids at two rental homes in Phnom Penh. The raids were conducted in conjunction with an investigation into illegal online gambling and Voice Over Internet Protocol (VOIP) scams, Khmer Times reported.

The suspects, including 19 women, were accused of operating an illegal online gambling operation and extortion. They allegedly used Cambodia’s VOIP system to extort money out of people living in China. The arrests took place in the Sen Sok and Tuol Kork districts of Cambodia following a tip from Chinese Interpol.

According to the tip from Chinese authorities, the individuals were posing as Chinese police, prosecutors, judges and bankers. They would use the facades to place phone calls to China in the extortion scheme. Lieutenant General Uk Haiseila of Cambodia’s General Department of Immigration said, “They are the group of Chinese mafias who have been hiding in Cambodia. They were arrested after our police raided their rental villas in Phnom Penh in collaboration with the Chinese police.”

During the raids, police confiscated VOIP telephones, mobile phones and other material evidence allegedly used for the calls. All of those arrested are being detained for questioning and could be deported to China sometime this week, according to the report. If they’re deported, Chinese Interpol has said that it would send a plane to Cambodia to collect the suspects so they can face a judge in China.