A powerful undersea earthquake struck off the southern coast of Alaska on Wednesday, setting off a tsunami advisory and prompting concern along the state’s remote peninsula region.

The tsunami warning was downgraded to an advisory after a 7.3 earthquake in Alaska.

The U.S. Tsunami Center said the warning was in effect from about 40 miles (64.4 km) southwest of Homer to Unimak Pass, a distance of about 700 miles.