A tsunami warning was briefly issued after an earthquake of magnitude 7.3 struck off Papua New Guinea.
The quake - which hit offshore 11.18 miles east-southeast of the town of Wau around 12.50pm local time - was at a depth of 85.2 km, the US Geological Survey (USGS) added.
The Pacific Tsunami Warning Center initially issued a tsunami warning but said about an hour later the danger had passed.
There were no immediate reports of casualties or damage and the PNG National Disaster Centre declined to comment until it had received a briefing.
Assessment teams have been deployed, according to RNZ Pacific.
Wau is an inland former gold mining town with a population of about 5,000, about 150 kms (93 miles) south-west of PNG's second-largest city, Lae.
A person who answered the phone at the Lae City Hotel said they the had felt the quake but there was no property damage.
"It's normal, the earthquake, here. The staff is okay. They just kept on going," the person said.
The hotel was fully booked but all the guests were out at the time of the quake, the person added.
People as far away as northern Australia are reported to have felt shockwaves, with the Bureau of Meteorology, Australia, tweeting there was "no tsunami threat to Australia".
Writing on Twitter, Zyra Hazel said: "Felt that earthquake but I guess my mind wasn't able to process it. Went back to sleep like nothing happened."
Another person said: "That adrenaline rush that turns you into a sprinter like you always dreamed of-during an earthquake!"
