A volcano in the eastern Aleutians is erupting again.
For the fourth time in less than a week, Bogoslof volcano has erupted prompting the Alaska Volcano Observatory (AVO) to issue its highest alert for air travel.
The observatory said the eruption on Dec. 26 threw ash 30,000 feet above the uninhabited island.
Experts cannot predict how long the eruption might last because there is no monitoring equipment on Bogoslof.