A major earthquake off Alaska with a preliminary magnitude of 7.2 has prompted a tsunami advisory for the state's southern peninsula.The tsunami advisory was downgraded from an initial tsunami warning Wednesday afternoon after the earthquake struck about 50 miles south of Sand Point,

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.