New Zealanders are still being targeted by mysterious calls from international numbers as part of an elaborate scam that has been running over the last few years.
Dubbed the "Wangiri" scam, which translates from the Japanese to "one ring and cut", it involves con artists leaving missed calls on the user's phone from an unknown international number. Should the user call back, they are charged premium rates of up to $50 a minute.
This is not the first time such scam hit New Zealanders. As recently as February last year, there were reports of similar scams.
Spark spokesperson Cassie Arauzo says Wangiri scams are a complex ruse.
"The Wangiri call is when a scammer will call from a premium number and purposely hang up after one or two rings," she told the Herald.
"Because calls are billed typically from the time of answer, these attempts have no cost to the attacker. They will typically target mobile phones, as there is a higher likelihood that a mobile phone has caller ID display.
''The goal for the attacker is to entice victims to call back the number upon seeing a missed call. The perpetrators make money by collecting revenue on these calls via the premium rates issued by the overseas telecommunications provider, or by scamming victims on the return calls."
Arauzo draws a distinction between wangiri ruse and the increasingly common robo dialler scams, which are also present in New Zealand.
"The auto-dialler system enables the caller to systematically auto dial a list of numbers. If it picks up human activity on the other end it can either connect you to a person, or if there isn't someone available, it will be silent and then hang up."
While Arauzo said Spark customers "don't appear to be reporting a surge of this type of scam activity," she did say the telco is always vigilant in keeping an eye on these issues.
"Spark plays an active role in limiting the number of scam calls out there. When a scammer uses one number continuously, we identify and block that number."
The same also applies Vodafone, whose spokesperson Elissa Downey says they're also keeping an eye on scam activity.
"Unfortunately the 'wangiri' scam hits our shores from time to time, but we are not seeing a surge in this type of scam at the moment," said Downey.
"Our best advice is to avoid answering those numbers or any number you don't recognise or expect a call from and let the call go to voicemail. That way you can check if the message is from someone you were expecting or actually want to hear from. If the caller does not leave a message, ignore it and don't call the number back."
Beyond the missed call variation of the "wangiri" scam, Downey also recommends keeping an eye out for other scams.
"Another one to watch out for is an unsolicited call and someone starts engaging with you," Downey told the Herald.
"Typically, with this type of scam they are calling from overseas but sometimes they might spoof a New Zealand number, fixed or mobile, and they either try to sell you something or ask you for money."
Downey recommends users treat the interactions exactly the same as they would an unsolicited email.
"Simply hang up and don't engage," she said.
"It is really important to always be on your guard with callers you don't know – if something seems a bit off or too good to be true, it usually is."
She also advises mobile users to notify their telco immediately if they have received a strange call or large charge.
"We work with the wider telco industry to block certain numbers from connecting through to customers phones if we know they are linked to a scam."
Downey finally recommends that users check the Consumer Protection website if they're in any doubt about whether something might be a scam.