Papua New Guinea earthquake
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A strong earthquake with a preliminary magnitude of 6.3 has struck off the town of Panguna in Papua New Guinea, seismologists say, but no tsunami warnings have been issued.

The earthquake, at 2:19 a.m. local time on Tuesday, was centered about 94 kilometers (58 miles) southwest of the town of Panguna on Bougainville Island. It struck about 30 kilometers (19 miles) deep, making it a shallow earthquake.

Shaking was felt on nearby islands but there was no immediate word on damage or casualties from the remote region. The Pacific Tsunami Warning Center said there was no tsunami threat from Tuesday's earthquake and no tsunami alerts have been issued.

The Pacific Tsunami Warning Center initially measured the earthquake at 6.7 before it was downgraded to 6.3 by the United States Geological Survey (USGS).

Earthquakes in the mountainous nation of Papua New Guinea, which is on the so-called 'Pacific Ring of Fire', do rarely cause damage or casualties as most structures in the region are light and flexible. This allows them to bend, rather than snap, when a major earthquake occurs.