A magnitude-8.0 earthquake was widely felt in communities along Alaska's sparsely populated Aleutian Islands on Monday, but there were no immediate reports of damage.
All tsunami advisories have been cancelled following the earthquake.
The National Tsunami Warning Center cancelled the last remaining advisory late Monday afternoon. At one point, areas stretching from Attu to Unimak Pass were under a tsunami warning or advisory, but the largest reported wave was about 18 centimetres.
The advisory area included Unalaska, a community of about 4,000 people and home to Dutch Harbor, one of the nation's largest fishing ports.
Emergency Measures British Columbia said there is no threat to other U.S. or Canadian areas along the North American Pacific coast.
The earthquake recorded at 12:53 p.m. local time was initially reported with a magnitude of 7.1, but Ruppert says that was upgraded to 8.0. The quake was centred about 20 kilometres southeast of Little Sitkin Island.
It was recorded at a depth of 100 kilometres, which is relatively shallow for an earthquake in the Aleutian Islands. The shallower the quake, the more likely it will be felt.
The National Tsunami Warning Center in Palmer, Alaska, issued a tsunami warning for coastal areas between Nikolski to Attu, on the Aleutian Islands. A warning means significant inundation is possible or occurring. Residents are being warned to move inland toward higher ground.
A tsunami advisory was also issued for coastal areas stretching from Nikolski to Unimak Pass. An advisory means strong currents or dangerous waves are expected, but widespread inundation isn't likely.
— with files from The Canadian Press