The Australian island of Lord Howe Island is on tsunami watch following a massive undersea earthquake in the Pacific.

People across the South Pacific – including in New Caledonia, Fiji, Vanuatu and New Zealand – were all told to avoid coastal areas due to the risk of tsunami waves following the 7.7 magnitude earthquake on Friday southeast of the Loyalty Islands in the French territory of New Caledonia.

Australia’s Bureau of Meteorology issued a tsunami threat for Lord Howe Island, 700km southeast of Brisbane, and warned the roughly 450 inhabitants to leave the water’s edge due to waves and strong currents.

“We haven’t moved to higher ground and we’re probably not going to,” said Damien Ball of the Thompsons General Store on Lord Howe Islands. “We’ve been through this numerous times before and nothing ever comes of it.”

Tsunami waves ranging from 0.3m to one metre above the tide level are possible for some coasts of Vanuatu, the Pacific Tsunami Warning Center (PTWC) said. Waves below that level are set for 25 island groups including Tonga and Tuvalu.

A 22 centimetre tsunami had been observed near New Caledonia, the threat alert added.

No waves have been observed that might threaten the Australian mainland.

Geoscience Australia said the quake hit at a depth of 31km, while the United States Geological Survey (USGS) had it at 38km.