Story highlights Bogoslof volcano erupted Saturday

It "remains at a heightened state of unrest," agency says

(CNN) An Alaskan volcano that has erupted several times since last year spewed an ash cloud up to 30,000 feet, leading to an aviation warning.

The Bogoslof volcano erupted Saturday, sending ash over the Aleutians Islands, the Alaska Volcano Observatory (AVO) said.

It "remains at a heightened state of unrest and in an unpredictable condition, and additional explosions producing high-altitude volcanic clouds could occur at any time," the observatory said.

An ash cloud from the erupting Bogoslof volcano, seen from nearby Unalaska island.

The volcano sits under the flight path of many flights from Asia to North America and its ash cloud could adversely affect aircraft.

"Ash and aircraft do not mix, as volcanic ash is abrasive, melts at jet engine temperatures, and can cause engine failure," the United States Geological Survey says.

Read More