The quake, at a depth of 28.2 miles, struck about 1:35 p.m. local time and was centered about 200 miles north-northeast of the capital of Port Moresby, the USGS said.
Papua New Guinea, like Indonesia, is on the Ring of Fire fault lines that are prone to frequent tremors and volcanic eruptions.
On Thursday, a 6.1-magnitude quake rattled Indonesia's tourist resort island of Bali, damaging a few buildings.
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