At least one person was killed after a powerful 7.3 magnitude earthquake struck off Vanuatu's coast on Tuesday.

The jolt was followed by a magnitude 5.5 aftershock near the same location.

"It was the most violent earthquake I've experienced in my 21 years living in Vanuatu and in the Pacific Islands. I've seen a lot of large earthquakes, never one like this," said Dan McGarry, a journalist based in the island nation.

Eyewitnesses reported extensive damage across the capital, Port Vila.

"There's people in the buildings in town. There were bodies there when we walked past," one resident told the AFP news agency.

Numerous airlines including Qantas, Virgin Australia and Fiji Airways halted or diverted flights to Port Vila's international airport.

Embassies damaged

Both the US and New Zealand confirmed extensive damage to their missions, which are housed in the same complex as the British high commission and French embassy. 

The US embassy announced in a statement that all its staff are "safe and accounted for."

"While the US Embassy building sustained significant damage, all personnel were able to safely evacuate the building," the embassy said.

Earlier, the embassy announced that its mission in Port Vila had sustained considerable damage and was closed until further notice.

"Our thoughts are with everyone affected by this earthquake," the statement added.

One local resident told the AFP that the ground floor of a building housing the US embassy had been crushed under higher floors.

"That no longer exists. It is just completely flat. The top three floors are still holding but they have dropped," they said. "If there was anyone in there at the time, then they're gone."

New Zealand's deputy prime minister Winston Peters said in a post on X that the country's High Commission building sustained "significant damage," as Wellington continues to monitor the "developing situation closely."

"We stand ready to help Vanuatu, and to respond to requests for assistance," he said.

Tsunami warning lifted

Footage posted online showed a building collapsed onto cars, and landslides blocking roads.

A tsunami warning was lifted two hours after the quake, while Red Cross teams are on standby to assist affected communities.

Waves of less than 30 centimeters (one foot) above the tidal level were predicted for other Pacific island nations including Fiji, Kiribati, New Caledonia, Solomon Islands and Tuvalu.

Vanuatu is located in the Southern Pacific and comprises 80 islands with a population of about 330,000 people.

ss/zc (AP, AFP, Reuters)