Civil Defence in Northland has apologised after a fault in its network set off tsunami sirens in the Whāngarei and Kaipara districts.
(File image) People shifted to higher ground at Whangārei Heads on 5 March in response to tsunami alerts following an 8.1 earthquake near the Kermadec Islands. Photo: RNZ / Nita Blake-Persen
The civil defence authority and Northland's main electricity provider Northpower apologised for last night's false alarm.
Northpower referred to a technical fault and, in a statement, said the provider was "very sorry for scaring everyone".
It follows last Friday's evacuation order for many coastal regions after a magnitude 8.1 earthquake near the Kermadec Islands.
Civil Defence said the authority "wholeheartedly apologise for this and the effect it had on people - we're very much aware of the responsibility to our communities that comes with the alerting platforms we manage, and this is even more true in the wake of the events of Friday 5 March."
Northpower, which installs and maintains the tsunami siren network in the region, said the tsunami sirens were unexpectedly activated due to a technical issue on its control systems.
"We are very sorry for scaring everyone with this false alarm. After last week's events we know this will have caused some concern. We are fully investigating the cause so this kind of false alarm does not occur again."
Northland Civil Defence leaders activated region-wide tsunami evacuation alerts following the string of large earthquakes on 5 March. Tens of thousands of people shifted to higher ground, including 15,000 Whangārei central city evacuees.