A spate of hacking attacks on Apple electronic devices in Australia has now reached New Zealand, Netsafe says.
Users of iPhone, iPad and Mac devices complained they were hacked and then locked themselves. A message demanding payment then appeared on the screen in order for them to be able to access their device again.
An online thread addressing the issue on Apple's official Support Communities website had been viewed more than 35,000 times since it was posted three days ago.
"We've received our first report of a hacked Apple ID and locked iPhone," NetSafe posted on their Facebook page on Tuesday.
"Please take 5 minutes to change your Apple password ASAP - especially if you use the same password on other online accounts."
If a passcode was set on the device, affected users could simply enter it, change their iCloud password and avoid having to deal with the ransom, the Sydney Morning Herald reported.
However if no passcode was set, users may have to erase and restore their devices.
Apple issued a statement to Fairfax on Wednesday stating that while its iCloud service had not been hacked, impacted users should "change their Apple ID password as soon as possible and avoid using the same username and password for multiple services".
Those requiring further assistance were advised to contact Apple or visit an Apple store.