Two aftershocks measuring higher than 5.0 followed the main quake.
The quake hit about 200 km (125 miles) southwest of the town of Rabaul, just before 7 a.m. local time (2100 GMT Wednesday) and was given an initial magnitude of 7.3.
A spokesman for PNG's National Disaster Management Office in Port Moresby said there were no immediate reports of damage or injuries, but claimed these usually take several hours to reach the capital after a major shake.
But it warned that "recent earthquakes in this area have caused secondary hazards such as tsunamis, landslides and liquefaction that might have contributed to losses".More news: Dow ends brutal session with 3.2% loss, Nasdaq -4.1%
A magnitude 7.0 quake struck remote New Britain island in Papua New Guinea on Thursday, the United States Geological Survey said.
"A tsunami threat exists for parts of the Pacific located closer to the natural disaster", the Pacific Tsunami Warning Center said in a bulletin.
The earthquake's tremors were felt as far as the holiday island of Bali, where locals and tourists were woken up by the sensation.
Hazardous tsunami waves from the natural disaster were possible within 300 km of the epicenter along Papua New Guinea coastlines, the Pacific Tsunami Warning Center said.More news: USA markets drop sharply as investors are spooked by rising rates
A teddy bear hangs next to quake and tsunami damaged property along the waterfront in Palu, Central Sulawesi, Indonesia October 10, 2018.
Papua New Guinea, one of the world's poorest countries, sits on the geologically active Pacific Ring of Fire and is still recovering from a magnitude-7.5 quake that hit some 900km to the west in February, killing at least 100 people.
The country is is still recovering from a magnitude-7.5 quake that hit around 900km to the west, which killed at least 100 people last February.
Indonesian authorities said at least three people were killed and four injured in the quake.More news: China is the key to beating climate change
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