A magnitude-8.0 earthquake was widely felt in communities along Alaska's sparsely populated Aleutian Islands, but there are no immediate reports of damage.
Alaska Earthquake Center seismologist Natasha Ruppert says communities that would have suffered damage are also under tsunami warnings, so people may not have been able to check for damage yet.
The earthquake recorded at 12:53 p.m. local time Monday was initially reported with a magnitude of 7.1, but Ruppert says that was upgraded to 8.0. The quake was centered about 13 miles southeast of Little Sitkin Island.
It was recorded at a depth of 60 miles, which is relatively shallow for an earthquake in the Aleutian Islands.
The National Tsunami Warning Center in Palmer, Alaska, issued a tsunami advisory for coastal areas between Nikolski to Attu, on the Aleutian Islands.
This story has been updated.