A tsunami warning was issued for southern Alaska on Monday after a major earthquake and large aftershock hit near the Alaskan Peninsula.
The warning was later downgraded to an advisory by the National Weather Service.
An initial earthquake with a 7.5 magnitude occurred around Sand Point, Alaska, a city on one of the Shumagin Islands, just before 1 p.m. local time (5 p.m. E.T.), according to the Official U.S. Geological Survey. An aftershock hit the area about 20 minutes later at a magnitude of 5.8, the USGS said.
The National Weather Service issued a tsunami warning for the Pacific coasts from Kennedy Entrance, Alaska to Unimak Pass, Alaska. Police in Homer, Alaska, asked anyone in the potential flooding zone to move to higher ground immediately in fear of a potential tsunami.
Sand Point, where the earthquake appears to have originated, is about 575 nautical miles southwest of Anchorage. The city is on Popof Island, one of 20 islands in the Aleutians East Borough south of the mainland.
USGS data showed at least eight aftershocks in the hour after the first quake, including five that measured between 5.2 and 5.9 in magnitude.
A powerful 7.8-magnitude earthquake hit Alaska in July, also triggering fears of a possible tsunami wave. That quake happened at 10:13 p.m., roughly 75 miles south of the community of Chignik.
Tsunami warnings were issued for about the same stretch of land, from Homer to Unimak Pass, and a tsunami did occur but posed no threat to locals.