PHNOM PENH, July 3 -- Cambodian police on Thursday raided three locations and arrested 80 Chinese nationals, who were involved in online telephone scams, said Lt. Gen. Chhay Sinarith, chief of the Interior Ministry's internal security department.

"We launched an operation simultaneously on Thursday afternoon and arrested a total of 80 Chinese nationals, including 23 females in Phnom Penh City, Takeo Province and Siem Reap Province," he told Xinhua.

He said the suspects are from the Chinese mainland and China's Taiwan.

"They are accused of using VoIP (Voice over Internet Protocol, a type of internet phone service) from Cambodia to threaten and extort money from victims in China," he said.

A number of telephones, computers and other electronic materials were seized, he said.

Telephone fraud has become a social security problem in China. Suspects often use overseas servers to make scam calls from, making it more difficult for the Chinese police to trace them.

Perpetrators usually phone their victims in China, claiming to be court or police officials, noting that the victims' bank accounts had been breached so that they have to transfer the money to a separate safe account.