The Alaska Volcano Observatory (AVO) issued its highest level of alert for aviation after reports surfaced about a brief eruption of Bogoslof volcano in the Aleutian Islands of Alaska. The volcano erupted Tuesday forming an ash cloud that rose to 34,000 feet, pilots reported.

The observatory issued a red alert, which defines a hazardous eruption being imminent, underway or suspected. Later Tuesday, the Bogoslof volcano's status was downgraded to orange, which means that the volcano "is exhibiting heightened or escalating unrest with increased potential of eruption" or that "an eruption is underway that poses limited hazards including no or minor volcanic-ash emissions."

While only 4,300 people live within 62 miles of the volcano, there is a lot of air traffic that crosses the Aleutian Islands — a chain of volcanic islands in the Bering Sea, belonging to both the U.S. and Russia. The last recorded eruption of Bogoslof was reportedly in 1992.

The volcano rises about 6,000 feet from the Bering Sea floor, but is only 300 feet above sea level at its highest point.

The observatory said in a statement that due to lack of ground-based monitoring equipment on Bogoslof volcano, it was difficult to predict future eruptive activity.

"AVO is unable to provide a forecast of future eruptive activity. We will monitor satellite images and data from distant seismic and infrasound instruments for indications of significant explosive activity," the observatory added.