Indonesia’s Mount Ruang volcano erupted Tuesday, prompting authorities to order an evacuation and forcing a nearby airport to close.

Indonesia’s geological agency raised the alert level on Sulawesi Island to its highest level, as the eruption blew clouds of ash, lava and rocks as high as two kilometers into the sky.

The agency urged residents living within a six-kilometer radius of Mount Ruang to evacuate. Officials at Sam Ratulangi International Airport, located about 95 kilometers southeast of the volcano in the provincial capital of Manado, shut down operations citing reduced visibility and the dangers volcanic ash poses to plane engines.

This is the second time this month Mount Ruang has erupted, forcing the Sam Ratulangi airport to close and hundreds of residents to evacuate.

Indonesia is prone to volcanic and seismic activity because of its location along the Pacific Ocean’s “Ring of Fire,” a series of seismic fault lines stretching about 40,000 kilometers from the western coasts of North and South America through Japan and Southeast Asia.

Some information for this report came from The Associated Press, Reuters.