A tsunami warning has been issued for all of the Pacific island of New Caledonia, after a shallow 7.6-magnitude quake struck off the country's coast, prompting warnings that hazardous tsunami waves up to three metres high could reach New Caledonia and Vanuatu.
In its latest advisory, the PTWC said tsunami waves had been observed.
A second powerful quake, of magnitude 7, has hit off New Caledonia, just hours after one measuring 7.6, according to the Pacific Tsunami Warning Center (PTWC).
"If you don't have time to prepare your evacuation, get more than 300m away from the coast and/or get to a height of more than 12m", warned the Directorate for Civil Protection and Risk Management of New Caledonia (DSCGR).
Tsunamis at minimal levels vary with slightly higher waves with minimal landfalls, and usually up to five minutes apart.
The Pacific Tsunami Warning Centre said tsunami waves could hit areas close to the French territory of New Caledonia, about 1,400km off Australia's coast. "The tsunami warning was what was different this time, though".
Residents of New Caledonia, which lies north of New Zealand, received an urgent text message directing them to go to refuges immediately.
The natural disaster - magnitude 7.6 - struck off the Pacific Ring of Fire territory on Wednesday.
The natural disaster had a preliminary magnitude of 7.5 and rattled the area just after 8 p.m., according to the United States Geological Survey.
Basile Citre, a municipal official on the Loyalty Island of Mare, said he had been in a meeting at the town hall when he felt a small tremor followed by a bigger shock.
Waves measured by quake monitors around the region only reached about 72cm on the island of Tanna, Vanuatu.
"The building shook, but there was no damage", he told AFP.
New Caledonia, with a population of 269,000 people, is a French Pacific territory.
Neighbouring Vanuatu also issued an evacuation warning.
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