SYDNEY (AP) — Australian police have revealed that Chinese students based in Sydney are being forced to stage photos and video of themselves bound and blindfolded in an extortion scam described as virtual kidnapping.

Eight students this year have fallen victim to the scams, which have netted criminal syndicates 3.2 million Australian dollars ($2.3 million), New South Wales state Police Detective Chief Superintendent Darren Bennett said Monday.

The students are typically telephoned by a Mandarin speaker who purports to be someone holding authority in China such as an embassy, police or tax official. They are told they risk deportation or arrest unless their families pay a ransom.

The students send images of themselves bound and gagged, move into hotels and cut off all communications.

“Our message today to everyone is that, if you receive a telephone call that encourages you to deposit money into a bank account by a person who’s pretending to be from a position of authority in China or another location, don’t pay any money, either hang the phone up, call the police, or call your university or educational facility to get some advice and counseling,” Bennett said.

New South Wales Assistant Police Commissioner Peter Thurtell said Chinese authorities had assured Australian police that under no circumstances would a government agency contact a student overseas to demand money.

The scam is becoming increasingly common as Australia-China relations continue to sour over issues including Australian calls for an independent investigation into the origins of and international responses to the coronavirus pandemic.

China is the largest source of international students attending Australian universities, and has warned students and tourists that they risk increased racism in Australia due to the pandemic.