The Inland Revenue Department is suffering from one of the most sophisticated attacks New Zealand has ever seen, as scammers use fake websites to steal personal information from unsuspecting Kiwis.

Believed to be coming from overseas, the attack has been branded as the most complex yet for government officials, who are currently working with the National Cyber Security Centre and New Zealand Police to combat the breaches.

As a result, the IRD is warning customers be alert for fraudulent emails from imitation websites claiming to be from the department.

Using a fake website bearing almost identical similarities to that of the IRD’s official website, the scam is offering Kiwis tax refunds via email, promising a quick return for refunds of $600 or less.

Yet the hoax, which tells users to submit their IRD numbers, bank details and personal information, appears worryingly genuine, hence the huge concern from IRD officials.

"It's the first one we have had as sophisticated as this," said an IRD spokesperson. “Although the pages look very similar to those on the Inland Revenue website, they are most definitely fake.

"It is important that people are aware that this is a deliberate attempt to use the Inland Revenue logo and brand to steal confidential and personal information."

Almost a month since the government department warned customers of fraudulent emails and imitation webpages, Jarrod Rendle, head of consumer information at the Ministry of Business, Innovation and Employment, accepts that the recent wave of attacks are the most dangerous yet.

“This latest one appears to be more sophisticated, as the website appears genuine," he said.

Reiterating the comments of Eleanor Young, Group Manager Customers Services, IRD, last month, Kiwis have been advised to stay vigilant when receiving alleged IRD correspondence.

"We want to make our customers aware that this is scam and a deliberate attempt to use the Inland Revenue logo and brand to steal confidential and personal information,” Young said last month.

“Although the pages look very similar to those on the Inland Revenue website they are most definitely fake.

"Any information that is given to these fraudsters can result in a business or individuals suffering identity and data theft."

Young added that the key thing to remember is that Inland Revenue will never issue a tax refund onto a credit card.

"These imitation website addresses are long and jumbled which show they are not authentic,” she said.

“We remind our customers that if anyone has replied to those behind these scams, and given money or their personal details, they should contact their bank or credit card provider immediately.”

So much so that the IRD has requested customers to keep their IRD numbers, tax information, online passwords and all other data safe at all times.

If you think someone is using an identity fraudulently, or attempting to steal your confidential information, then let the department know.