In Alaska, small tsunami waves measuring under a foot above tide level were observed in Sand Point, Old Harbor, King Cove, Kodiak, Unalaska and Alitak Bay, according to the US National Tsunami Warning Center (NTWC).
There were no immediate reports of injuries or damage to property. Several Alaskan coastal communities were evacuated following the quake. Among them was Seward on the Kenai Peninsula, south of Anchorage, where sirens blared and residents were told to move to higher ground.
The U.S. Geological Survey (USGS) said the quake, which struck at 10:15 pm local time (0615 GMT Thursday), was at a depth of 35 km. It struck about 91 km east-southeast of Perryville, about 800 km (500 miles) from Anchorage, Alaska's biggest city.
The U.S. states of California, Oregon and Washington and the Canadian province of British Columbia were not expected to see any significant tsunami threats, Dave Snider, tsunami warning coordinator with the NTWC, told Reuters.
"There might be some minor damage in some places (in Alaska), but a significant tsunami and significant damage from something like that is not expected," Snider said.
While shallow earthquakes near populated areas can be dangerous, in this case the shallow quake posed less of a threat because they do not usually generate large tsunamis.
"That's really fortunate in this case, because 8.2 is really strong enough to make a sizable wave, especially in that location of the world," Snider added.
The Pacific Tsunami Warning Center (PTWC) cancelled warnings issued for Hawaii and the US Pacific territory of Guam, while the public broadcaster NHK said there was no risk to Japan. Authorities in New Zealand also said they did not expect any flooding in coastal areas.
According to the USGS, the quake was followed by over 25 aftershocks in the region, with two around magnitude 6.0.
The quake was the seventh largest in US history, tied with another Alaskan quake from 1938, according to USGS data. It is also the largest quake in North America since an Alaskan quake of 8.7 magnitude in 1965, according to USGS data.