The New Zealand Stock Exchange board is shown on the side of Jarden Building in central Auckland, New Zealand, Friday, Aug. 28, 2020. New Zealand's government and overseas spy agency are getting involved after ongoing cyber attacks have disrupted the New Zealand stock exchange several times this week. (Greg Bowker/New Zealand Herald via AP)

New Zealand's justice minister says the nation is confronting cyber attacks on an unprecedented scale, targeting everything from the stock market to the weather service.

Andrew Little said in an interview with The Associated Press on Wednesday that tracking down the perpetrators of the attacks in recent weeks would be extremely difficult, as the distributed denial of service attacks are being routed through thousands of computers.

One line of investigation is the emails sent to people in some of the targeted organizations demanding a ransom in exchange for stopping the attacks, Little said. The official advice is to never, ever pay a ransom.

Little said he's been told that the sheer volume of data used by the attackers is unprecedented. New Zealand's foreign spy agency, the Government Communications Security Bureau, is helping with the investigation and working to protect companies targeted in what it says appears to be part of a global campaign.

The attacks stopped share trading for up to several hours at a time over four days last week. Private company NZX, which hosts the , said it halted trading to maintain market integrity because the attacks prevented it from publishing market announcements.

Little said the attackers had found vulnerabilities in the 's operations.

"That motivated them to continue the attack, and they picked on other organizations as well," he said.

One of those was the bank TSB, which was hit Tuesday. Chief Executive Donna Cooper said the attack disrupted some of its services but it had a plan in place and the bank remained sound.

Another bank, Westpac, said it successfully repelled an attack two weeks ago and hadn't been hit again since. News organizations Stuff and RNZ reported they had repelled attacks over the weekend.

The weather organization MetService was also hit this week, switching its website to a stripped down version in order to stay online.

NZX said that, despite more attacks on its website, so far this week it has been able to trade uninterrupted.

"NZX has been advised by independent cyber specialists that the attacks last week are among the largest, most well-resourced and sophisticated they have ever seen in New Zealand," chief executive Mark Peterson said in a statement.

Little said the attacks were a wake-up call to all organizations with customer-facing websites. Only a few organizations seem to have been targeted at any one time and most have been able to repel the attacks, giving him confidence the country can move past them.