Alaska earthquake prompts brief tsunami warning

A major earthquake shook parts of Alaska early Friday, sparking a tsunami warning for the Aleutian Islands that was canceled an hour later.

The earthquake was measured at a preliminary magnitude of 7.1, before being lowered to a magnitude of 6.8, the U.S. Geological Survey says.

Alaska's Aleutian Islands sit on the Pacific Ring of Fire, a "horseshoe-shaped seismic belt 25,000 miles long where most of the world's earthquakes and volcanic eruptions occur," Agence France-Presse reports.

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The tsunami warning was canceled after only a small wave came ashore near the hamlet of Atka, Alaska, the closest community affected by the quake and home to only about 60 people, the Associated Press says. 

Some people in Unalaska/Dutch Harbor, Alaska, the largest community in the area affected by the earthquake and tsunami warning, headed to high ground after being awoken by sirens from the tsunami warning system.

The epicenter of the quake was in waters near a sparsely populated part of the Aleutian Islands, and there were no immediate reports of damage, Reuters reports.

The earthquake struck at about 2:55 a.m. AKDT, and was 22.1 miles deep, according to the U.S. Geological Survey.

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