Buildings were damaged and widespread power outages were reported in the Solomon Islands capital, Honiara, after two earthquakes struck the southwest coast on Tuesday.
The first 7.0-magnitude earthquake briefly prompted a tsunami warning from the United States Geological Survey, but that warning was withdrawn soon after.
A second earthquake, with a magnitude of 6.0, occurred about 30 minutes later.
There was a power outage in some areas of Honiara and the Solomon Islands Broadcasting said in a statement that all radio services were off the air.
Australian Prime Minister Anthony Albanese said the roof of the Australian high commission annex in Honiara had collapsed, “which points to potential damage across the city”.
“We have contacted Prime Minister Sogavare to indicate once again that Australia is ready to help.”
Albanese said all staff at the Australian high commission were safe, but confirmed that the safety of all Australians in the Solomon Islands was difficult because telecommunications had been disrupted.
The quake near Malango was shallow, with a depth of 10 km, the USGS said.
People reported violent shaking that threw televisions and other objects to the ground.
Freelance journalist Charley Piringi said he was outside a warehouse next to a primary and secondary school on the outskirts of the capital, Honiara, when the quake struck and sent children running.
“The earthquake shook the place,” he said. “It was a big one. We were all shocked and everyone is running around.”
The nation’s attorney general, John Muria, posted images on social media of office files spilling out of large metal filing cabinets.
“This was a big one,” Joy Nisha, a receptionist at the Heritage Park Hotel in Honiara, told AFP news agency. “Some of the stuff in the hotel fell over. Everyone seems fine, but they’re panicking.”
An AFP reporter in the capital said the tremor lasted about 20 seconds.
Reuters and Agence France-Presse contributed to this report