An earthquake shakes the country of Vanuatu, an island in the Pacific Ocean, and fears of deaths, and damage to the American embassy.

Wellington, New Zealand – Injured people were arriving at a hospital in Vanuatu as unconfirmed reports of casualties emerged after a powerful earthquake measuring 7.3 on the Richter scale struck the South Pacific island nation off the coast on Tuesday.

The tsunami warning was canceled less than two hours after the quake. As communications continued to be cut off hours after the quake and official information was scarce, witness accounts of the victims began to appear on social media and through irregular phone calls.

The quake occurred at a depth of 35 miles and was centered 18 miles west of Port Vila, the largest city in Vanuatu, a group of 80 islands inhabited by about 330,000 people. The tremor was followed by a 5.5 magnitude aftershock near the same location.

It was not immediately clear how much damage had been caused, as phone lines and government websites remained down and official channels were not updated, but reports of widespread devastation leaked on social media and in interviews.

Dan McGarry, a journalist based in Port Vila, told the Associated Press that he heard about someone dying in the quake from a police officer outside Vila Central Hospital. He added that McGarry saw three people on stretchers “in apparent distress.”

He added that doctors were working “as quickly as possible” at the triage center outside the emergency ward. McGarry said the nation was not prepared for a large-scale casualty event.

A video posted by the Vanuatu Broadcasting Corporation showed crowds outside the hospital. The phone numbers of the police, hospital and other public bodies were not reached. There were no official reports of casualties.

Reports of people trapped inside the buildings have also not been confirmed.

A video posted on social media showed collapsed buildings in Port Vila, including one that collapsed onto cars. A Fiji Red Cross spokesman said the head of the relief agency’s office in Vanuatu reported widespread damage before communications were cut off.

New Zealand’s Ministry of Foreign Affairs said a four-storey building housing a number of embassies in Port Vila, including those of the United States, Britain, France and New Zealand, suffered extensive damage.

A video posted on social media showed the building sustaining some damage, including broken windows and debris falling from the walls to the ground. Other photos and videos showed items and shelves falling to store floors and landslides that appeared to block some roads.

Agence France-Presse said that the pictures it published showed the ground floor of the building completely leveled.

The basement “no longer exists,” Vanuatu resident Michael Thompson told AFP via satellite phone after photos of the devastation were posted on social media. “It’s completely flat. The top three floors are still standing but they’ve fallen.”

But AFP reported that the US Embassy in Papua New Guinea said all staff at the US Embassy in Vanuatu were “safe and identified”.

“While the US Embassy building sustained significant damage, all employees were able to safely evacuate the building,” she said in a statement on social media, adding that the embassy would be closed until further notice.

Katie Greenwood, head of the Fiji-based Red Cross regional office for Asia and the Pacific, told the Australian Broadcasting Corporation that Port Vila’s downtown area was full of large buildings and hotels.

She added: “We have not yet heard of any casualties, but I would be shocked if we did not hear that bad news coming from Port Vila at some point.”

McGarry said a “massive landslide” at the international shipping terminal would likely hamper the country’s recovery. He added that the airport runway was also damaged.

Vanuatu’s location in a subduction zone – where the Indo-Australian tectonic plate moves beneath the Pacific plate – means that earthquakes of magnitude greater than 6 are not uncommon, and the country’s buildings are designed to withstand earthquake damage.

“I think it could have been worse,” McGarry said. But he said this was the most serious he had been exposed to in his 21 years in Vanuatu “by far”.

In the hours after the quake, the US Geological Survey said the tsunami threat had passed. The agency had previously warned of waves reaching 3 feet above tide level.

Authorities in Australia and New Zealand, located in the Pacific Ocean, said there was no threat of a tsunami occurring in their countries.