A violent 7.5 magnitude earthquake struck an island chain off the north coast of Papua New Guinea late Tuesday, knocking out power and sending residents fleeing for safety.
The shallow quake occurred around 11pm (1300 GMT), some 44 kilometres (27 miles) northeast of Kokopo on New Britain island, the US Geological Survey said.
"It was massive, absolutely massive. Very scary," Megan Martin, the managing director of the Ropopo Plantation Resort in Kokopo, told AFP.
"There does not appear to be any damage, but we are out checking."
An AFP reporter based in Kokopo said electricity went off in the town after the quake struck and people ran from their homes for safety.
There were no initial reports of serious damage but the full picture may not become clear until daylight.
Aftershocks are still being felt long after the initial quake, as residents sat in darkness, fearful of tsunami waves.
The Pacific Tsunami Warning Centre had forecast a surge of up to one metre in height, that could eventually reach as far away as Japan, Taiwan, the Philippines and Indonesia.
Scientists do not have sea level gauges in this remote corner on the Bismark Archipelago, but they later said they believed the threat had passed.
Kokopo is no stranger to natural disasters. It sits in the shadow of nearby Rabaul, which was devastated by twin volcanic eruptions in 1994.
Earlier this year, weeks of heavy rains killed at least nine people, with many more families left homeless without access to safe drinking water.
Papua New Guinea is well within the Pacific "Ring of Fire" a hotspot for seismic activity due to friction between tectonic plates.
Just weeks ago a 7.2 earthquake knocked items off shelves in Port Moresby -- far from the epicentre -- and was felt as far away as Australia.
A 7.5-magnitude quake hit the rugged highlands region in February 2018 that triggered landslides, burying homes and killing at least 125 people.
The scale of that disaster did not become apparent for days due to PNG's poor communications and infrastructure.
Along the South Solomon trench, an area of the Pacific that includes Papua New Guinea, there have been more than a dozen quakes of magnitude 7.5 or more recorded since 1900, according to USGS data.