- Tsunami warnings went out for a number of South Pacific communities.
- Earthquakes measuring 7.4, 7.3 and 8.1 were recorded.
- Waves of up to 3m were possible, authorities said.
Tsunami sirens rang out in coastal communities across the South Pacific on Friday, as a cluster of powerful earthquakes triggered warnings for tens of thousands of residents to rush to higher ground.
Tsunami alerts were issued in countries as far apart as Peru and Australia, after a trio of large quakes measuring 7.4, 7.3 and 8.1, plus dozens of powerful aftershocks, struck near New Zealand's remote Kermadec Islands.
No damage or injuries were reported from the quakes.
But authorities warned waves of up to 3m were possible in New Caledonia and Vanuatu, where residents in the capital Port Vila received SMS messages ordering them to "move to higher grounds".
Eyewitnesses in the city said a small initial surge was visible, but did not appear to cause any damage.
In Noumea, capital of the French territory of New Caledonia, warning sirens sounded.
Emergency services spokesperson Alexandre Rossignol took to local radio to warn people to "leave beach areas and stop all water activities and should not pick their children up at schools to avoid creating traffic jams".
Several other regions were warned of lesser, but still potentially dangerous surges, including New Zealand where an evacuation order for a swathe of coastal communities was cancelled after a few hours.
Fiona Rudsdale, who runs the Whangarei Central Holiday Park on New Zealand's North Island, slept though the initial quake but was woken by tsunami warning sirens.
She immediately began organising the evacuation of around 30 guests from the caravan park to a nearby hilltop.
"We took them up to the top of Morningside Park, you can look down on the town from there," she said.
"We put on some food and drink, it all went pretty smoothly. You've still got a couple of idiots in town drinking around but mostly everyone's behaving themselves and doing what they're told."
Emergency Services Minister Kiri Allan said the entire town of Opotiki, about 4 000 people, had emptied out as coastal communities responded to the warnings.
"Very swiftly people pulled themselves together, got their backpacks, got into cars and congregated either inland or up high and are now watching it unfold," she said.
The local coastguard ordered hundreds of boats still on the ocean to deeper waters as a precaution.
Thousands of kilometres away on the French Island Tahiti there were heavy traffic jams as police prevented people from travelling to potentially impacted areas.
Some people were mildly dehydrated during the wait, and local authorities have since lifted the tsunami warning.
The largest of the quakes struck around 1 000km off the New Zealand coast at 08:28 (19:28 on Thursday GMT), the US Geological Survey said.
It was preceded by two seismic jolts that were also enormously powerful, in an unusually strong cluster even for the Pacific ring of fire, where the Earth's tectonic plates collide.
"On average, a magnitude eight or larger earthquake only occurs once a year anywhere in the world, so this is a significant earthquake and at a depth and magnitude to potentially generate a tsunami," said Adam Pascale, chief scientist at ESS Earth Sciences.
New Zealand's National Emergency Management Agency said the remoteness of the quakes did not minimise their potential impact.
"The earthquake may not have been felt in some of these areas, but evacuation should be immediate as a damaging tsunami is possible," it said.
But Prime Minister Jacinda Ardern of New Zealand was among those given an early morning wake-up.
"Hope everyone is ok out there - especially on the East Coast who would have felt the full force of that earthquake," she posted on Instagram after the initial shake at 02:27.
The South Pacific nation recently marked the 10th anniversary of the Christchurch earthquake, when a 6.3 tremor resulted in 185 deaths in the South Island city.