A magnitude 7.7 earthquake has struck the South Pacific east of Australia, prompting brief tsunami warnings for Vanuatu, Fiji, New Zealand, New Caledonia and Kiribati.

The earthquake struck near the Loyalty Islands at a depth of about 38 km (24 miles), according to the United States Geological Survey (USGS).

A tsunami warning of up to 1 m (3 ft) was issued for Vanuatu. That was revised down much lower than the initial forecast by the Pacific Tsunami Warning Center, which said waves of 3 meters could hit the island nation.

It said “dangerous tsunami waves” were possible along all coasts within 1,000km of the epicenter, with the potential for small waves to hit Fiji, New Caledonia, Kiribati and New Zealand.

About three hours after the earthquake, the US Tsunami Warning Center announced that there was no longer a threat.

“Based on all available data, the tsunami threat from this earthquake has now passed,” the center said.

The initial tsunami warning prompted authorities in New Caledonia to order the evacuation of coastal areas on Friday, a government official said, according to AFP, with at least one beach evacuated.

The seismic activity triggered warning sirens and people were ordered to immediately leave areas near the island’s coastline, Col. Marchi Lecchia, a security official, told a local radio station.

Small tsunami waves were seen in Vanuatu shortly after the warnings were issued, the Pacific Tsunami Warning Center said.

Tsunami waves smaller than 0.5 m (1.5 ft) were measured off Lenakel, a port city in the island nation, while smaller waves were measured elsewhere off Vanuatu and off New Caledonia.

New Zealand’s National Emergency Management Agency (NEMA) said it was still assessing the potential for a tsunami.

Its civil defense agency issued an advisory saying New Zealand’s coastal communities could experience “strong and unusual currents and unpredictable” waves on shore.

NEMA said the first tsunami could reach New Zealand’s coast by 5pm local time in areas around the North Cape. He warned people not to wander in the water, off beaches and shores.

“People on boats, paddleboards and marinas should leave their boats/vessels and move ashore. Do not return to the boats unless instructed by officials,” NEMA said.

The epicenter of the powerful earthquake was southwest of Fiji, north of New Zealand and east of Australia, where the Coral Sea meets the Pacific Ocean.

The Australian Bureau of Meteorology has issued a marine tsunami warning for Lord Howe Island, which lies between New Zealand and Australia and is part of the Australian state of New South Wales.

“For the marine environment of Lord Howe Island, there is the potential for dangerous rips, waves and strong ocean currents, as well as some localized overtopping to the immediate coast,” the Bureau of Meteorology said.

“These conditions are expected to begin after 16:15 (local time) on Friday and last for several hours. It is important to exercise caution and be aware of these potential hazards if you plan to participate in any marine activities during this time.

The Hawaii Emergency Management Agency said no tsunami threat is yet expected for Hawaii from the earthquake.