A powerful 7.1-magnitude earthquake jolted Papua New Guinea on Friday and was followed by a 6.7-magnitude tremor, AFP reports.
But no Pacific-wide tsunami warning was sounded, US officials said.
The US Geological Survey (USGS) said the first quake, originally put at 7.3 magnitude but later revised down, struck 57 kilometres off the town of Panguna on the remote and volcanic Bougainville island.
The second hit about an hour later 96 kilometres from Panguna, the USGS said, adding that both quakes had an estimated depth of about 50 kilometres.
Geoscience Australia estimated the first quake at 7.4 magnitude and said the tremor, which hit close to the neighbouring Solomon Islands, was believed to be in the “shallow” range.
"They would have gotten a strong shake across the island, and there’s the possibility of some damage,” David Jepsen from Geoscience Australia said.
The Hawaii-based Pacific Tsunami Warning Center ruled out the threat of a Pacific-wide destructive tsunami after both quakes but Jepsen cautioned that there was a "possibility of a local tsunami" in PNG.