A magnitude 3.5 earthquake occurred at Great Sitkin Volcano on Friday.
Since then, seismic activity has returned to lower levels, and no eruptive activity has been detected at the volcano – located 26 miles east of the community of Adak.
Hans Schwaiger, a scientist with the Alaska Volcano Observatory (AVO), said it appears the shallow earthquake was an isolated event, although small local earthquakes have continued over the past day.