A 7.8-magnitude earthquake has struck the Alaskan peninsula, reports the US Geological Survey (USGS).
The quake occurred at a depth of 10 km (6 miles), said the USGS, some 75 miles south of the city of Chignik.
The US National Tsunami Warning Center has since published a tsunami warning for Chignik, South Alaska, the Alaskan peninsula, and the Aleutian Islands.
Government agencies are believed to be evaluating the tsunami threat to Canada and the US mainland.
An earlier alert from the GFZ German Research Centre said the quake was 7.4-magnitude, which was later revised-upwards.