WELLINGTON: Tens of thousands of coastal residents in New Zealand, New Caledonia and Vanuatu fled for higher ground on Friday (Mar 5) as a cluster of powerful earthquakes sparked a Pacific-wide tsunami alert.
Warning sirens sounded across Noumea as authorities ordered evacuations amid fears that waves of up to 3m were headed towards the French territory.
"People must leave beach areas and stop all water activities, and should not pick their children up at schools to avoid creating traffic jams," emergency services spokesman Alexandre Rosignol told public radio.
In New Zealand, communities along stretches of the North Island were warned to flee as tsunami alert sirens wailed after an 8.1-magnitude quake, which followed earlier tremors in the same region measuring 7.4 and 7.2.
"Do not stay at home," the National Emergency Management Agency said.
"People near the coast ... must move immediately to the nearest high ground, out of all tsunami evacuation zones, or as far inland as possible."
At 1.27pm (8.27am, Singapore time), the agency lifted evacuation orders and declared "the largest waves have now passed".
"All people who evacuated can now return," it said.
It cautioned that "strong and unusual currents and unpredictable surges" would continue for several hours.
Earlier, an emergency alert was issued for all coastal areas around Auckland, a city of 1.7 million, where people were told to stay away from the water's edge. There were no reports of damage or casualties from the quakes.
"The first wave may not be the largest," said Bill Fry, a seismologist at geoscience body GNS, told a televised news conference in the capital, Wellington.
"Tsunami activity will continue for several hours, and the threat must be regarded as real until this warning is cancelled," he added.
The largest of the quakes struck around 1,000km off the New Zealand coast at 8.28am (3.28am, Singapore time), 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.
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.
COASTAL RESIDENTS ON ALERT
The US Pacific Tsunami Warning Center said Vanuatu and New Caledonia were likely to experience the largest waves, measuring up to 3m.
"Based on all available data, hazardous tsunami waves are forecast for some coasts," it said.
It said initial smaller waves were already reported in Tonga, and small waves were also possible as far afield as Japan, Russia, Mexico and the South American coast.
Australia issued a marine tsunami threat for Norfolk Island, a tiny Australian territory with about 1,750 residents, but said there was no threat to the mainland.
Norfolk Island residents in areas threatened by land inundation or flooding were advised to go to higher ground or inland, the Bureau of Meteorology said. Residents were also told to get out of the water and move away from the water's edge at beaches, marinas, coastal estuaries and rock platforms.
Chile said it could experience a minor tsunami.
The US Pacific Tsunami Warning Center cancelled a tsunami watch on Thursday for Hawaii. The agency also previously cancelled a tsunami warning it had issued for American Samoa.
In American Samoa, officials rang village church bells and police in marked vehicles and fire trucks used loudspeakers to spread word of the threat because the territory's regular outdoor warning system has been out of commission since last year.
Repairs have been on hold because flights to American Samoa were suspended amid the pandemic and technicians have been unable to make the trip.
Residents weren't taking any chances after a tsunami in 2009 killed 34 people in American Samoa and caused major damage.
The 7.2 magnitude earthquake that struck off the east of New Zealand's North Island was felt by more than 60,000 people across the country with many describing the shaking as "severe". Aftershocks were still being recorded in the area.
No damage or injuries were reported from the earlier quakes, both of which generated tsunami warnings that were later lifted.
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 2.27am (9.25pm, Singapore time).
New Zealand experiences frequent seismic and volcanic activity but Emergency Services Minister Kiri Allan said she had never before experienced such a strong sequence of earthquakes.
"This has been an extraordinary morning for many New Zealanders up and down the country," she said.
"From 2.30am this morning they have been up, worried about their homes and their families."
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.