Seismologists say a cluster of earthquakes has been detected at a remote volcano in Alaska's western Aleutian Islands. The Alaska Volcano Observatory says the quakes began Wednesday evening at Little Sitkin Volcano and are continuing as of Thursday morning. No eruption has been detected.

Scientist in charge John Power says there is no direct link to the swarm of earthquakes at Little Sitkin and a cluster of quakes that shook California's Imperial County this week.

Powers says Little Sitkin is on an uninhabited island and is far from any populated areas. He says the seismic activity is unusual for Little Sitkin, which may have last erupted in the early 1900s.

Powers says the concern about an eruption would be the possible threat posed to aircraft by airborne ash.