Vocus, the third largest internet provider in New Zealand, faced a cyberattack triggering a widespread internet outage.

The ISP with a strong fiber network on Friday said its systems blocked a denial of service (DDoS) attack on one user but in doing so caused some Vocus customers in the country’s largest cities – Auckland, Wellington and Christchurch – to suffer outages.

Vocus said it resolved the issue within 30 minutes. A DDoS attack is a way in which hackers disrupt a server by overwhelming it with a flood of internet traffic.

“We are working closely with the vendor of this platform to understand why this occurred,” said Vocus spokesperson.

Vocus did not reveal the name of the cyber security partner or the company that supplies its Internet network. Vocus has earmarked an annual Capex of $185-200 million for the fiscal 2021.