Buildings in Vanuatu damaged and casualties reported as ...

Injured people have been arriving at hospital, reports have said, on the South Pacific island of Vanuatu after a powerful earthquake struck just off its coast, damaging buildings and causing landslides.

The tremor was centred near the capital, Port Vila, the largest city on the group of 80 islands, at a depth of 35 miles (56km) below the earth's surface on Tuesday, the US Geological Survey (USGS) said.

It was followed by a magnitude 5.5 aftershock at the same spot and the shudders continued throughout the afternoon and evening local time.

Dan McGarry, a journalist based in the city, told The Associated Press he heard of one death in the quake from a police officer outside Vila Central Hospital where he saw three people on gurneys "in obvious distress".

Doctors were working "as fast as they could" at a triage centre outside the emergency ward, he added. But the nation is not equipped for a mass casualty event, Mr McGarry said, adding that the airport's runway is also damaged.

Mr McGarry also uploaded footage of a "massive" landslide at the international shipping terminal.

A clip on state broadcaster VBTC's Facebook page showed dozens of people outside the hospital, many lying on hospital gurneys waiting to be seen.

Reports of people trapped inside buildings could not immediately be confirmed.

Communications with the country, which is home to around 330,000 people across its islands, were knocked out by the quake, making official information scarce.

Vanuatu government websites were offline in the aftermath of the quake and phone numbers for the police and other public agencies did not connect.

Other videos posted online showed extensive damage to buildings, as well as vehicles and roads.

Soldiers were at the site of one collapsed building, whose awning had fallen onto cars, crushing them.

A building housing a number of diplomatic missions in Port Vila - including those of the US, Britain, France and New Zealand - was significantly damaged, New Zealand's Foreign Ministry said.

Footage showed its windows had buckled and debris had crumbled from walls to the ground.

Officials were in the process of accounting for New Zealand High Commission staff, a spokesperson said.

Other photos and videos showed items and shelves that had tumbled to the floors of shops and landslides that appeared to block some roads.

Penny Wong, Australia's foreign minister, told reporters that Australian High Commission staff were safe as she offered the country's help to Vanuatu.

New Zealand's foreign minister Winston Peters added 45 New Zealanders were registered as being in Vanuatu and said his government was "deeply concerned" about events there.

A Red Cross spokesperson in Fiji said the head of the aid agency's Vanuatu office had reported widespread damage before communications were cut off.

The World Health Organisation (WHO) said it was "closely monitoring the situation".

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The USGS issued a tsunami warning for waves of up to 30cm (11 inches) to 1m (39 inches) above the tide level for some coasts on Vanuatu but the warning was called off less than two hours after the quake.

Warnings of smaller waves were issued for a number of nearby Pacific Island countries, including Papua New Guinea, Fiji and Solomon Islands.

Authorities in Australia and New Zealand said there was no tsunami threat to their countries.