Tsunami alert in Australia, New Zealand after magnitude 7.2 quake strikes southeast of Loyalty Islands

New Zealand authorities early on Thursday urged residents along its northern coast to avoid beaches and shore areas after a strong earthquake struck southeast of the Loyalty Islands in the Pacific.

The New Zealand National Emergency Management Agency said people should get out of the water, off beaches and away from harbours, rivers and estuaries in areas from Ahipara to Bay of Islands, Great Barrier Island and from Matata to Tolaga Bay. "We expect New Zealand coastal areas to experience strong and unusual currents and unpredictable surges at the shore," the agency said in a statement.

Meanwhile, Australia's Bureau of Meteorology said there was a tsunami threat to offshore Australian islands and territories. The European Mediterranean Seismological Centre (EMSC) said the 7.7 magnitude quake's epicentre was 417 km (258 miles) east of Tadine, New Caledonia, and was at a depth of 10 km (6.2 miles). 

The quake, which was upgraded from an earlier magnitude of 7.2, followed at least three other tremors in the region with magnitudes ranging from 5.7 to 6.1 in a span of just over an hour.

The US Tsunami Warning System said a tsunami watch was in effect for American Samoa and that there was potential for tsunamis in other regions including Vanuatu, Fiji and New Zealand. Waves reaching up to a level of 1 metre (3.3 feet) above the normal tide level are possible for some coasts of Vanuatu, Fiji and New Zealand, it added.