This article is more than 5 years old

This article is more than 5 years old

Planes are being warned to avoid airspace near an erupting Alaska volcano as it spews ash 30,000ft above sea level.

The National Weather Service said on Saturday ash was being blown to the west and northwest of Pavlof Volcano.

Pavlof began erupting three days ago, pushing lava out from a vent near its summit. On Friday, the ash cloud reached 16,000ft.

Alaska Volcano Observatory geophysicist Dave Schneider said the eruption intensified at 6am on Saturday, sending the ash cloud higher. Schneider said it was not clear how long the eruption will last, as Pavlof’s eruptions may last for weeks or months with varying levels of intensity.

Pavlof is Alaska’s most active volcano. It sits along international air routes connecting Europe, North America and Asia.