Police are urging people to be on high alert for virtual kidnapping scams that continue to target international students across NSW.
Three incidents have been referred to the State Crime Command's Robbery and Serious Crime Squad so far this month - those cases in Sydney.
But Wednesday's warning is also of concern to the Hunter, where there is a population of international students.
According to the University of Newcastle's latest annual report, the uni has more than 5000 international enrolments.
In the statewide warning issued on Wednesday, police said investigators believed the modus operandi of the scammers was changing.
A virtual kidnapping is a sophisticated extortion scam that involves young victims faking their own kidnappings following phone calls from fraudsters - who then demand ransom payments for their safe release from relatives.
Investigators have been told that initial contact is made through a phone call from someone usually speaking in Mandarin and claiming to be a representative from a Chinese authority, such as the Chinese embassy, consulate or police.
The caller then convinces the victim that they have been implicated in a crime in China, or that their identity has been stolen, and that they must pay a fee to avoid legal action, arrest or deportation.
Using technology to mask their physical locations, scammers encourage victims to continue communications through various encrypted applications such as Skype, WeChat and WhatsApp.
The victim is then threatened or coerced into transferring large amounts of money into unknown offshore bank accounts.
In some instances, victims are convinced to fake their own kidnappings - known as a virtual kidnapping.
Scammers instruct victims to cease contact with their family and friends, rent a hotel room and take photographs or video recordings that depict them bound and blindfolded. These files are then shared with the victim's relatives overseas.
When the victim's parents are unable to establish contact with their child in Australia, they send large ransom payments in exchange for their 'release'.
The caller will continue to make threats and ransom demands until they are unable to obtain any further payments, often resulting in the victim's family making contact with police.
Incidents of a similar nature have been reported to interstate and international law enforcement agencies, netting millions of dollars from victims around the world.
Robbery and Serious Crime Squad commander Detective Superintendent Joseph Doueihi said the modus operandi of the scammers appeared to be changing.
"Virtual kidnappings have developed considerably over the last decade by transnational organised crime syndicates, and they continue to become more sophisticated," he said.
"In some cases, we're seeing evidence of the scammers talking to their victim for months on end.
"We've also seen a couple of cases where the victim has eventually been coerced into then becoming the perpetrator and acting as a Chinese official to scam more students."
Detective Superintendent Doueihi said anyone who received a call from someone claiming to be a Chinese authority should be hyper-vigilant in checking authenticity.
"While we are working with our law enforcement counterparts to investigate the origins of these scams, we are urging the community to heed our warnings not to respond to the caller's demands," he said.
"If you are ever on the receiving end of similar correspondence, the best thing to do is contact the Chinese consulate to verify the claims, as well as report the matter to the NSW Police Force.
"We want to remind victims there is nothing to be ashamed of coming to the police, as we continue to pursue every investigative avenue available to us to put an end to these types of scams."
