The Philippines’ most active volcano has begun erupting again, after thousands of people on the main island of Luzon were earlier forced to evacuate.

A photo of Mayon volcano published late Monday local time by the Philippine Institute of Volcanology and Seismology (PHIVOLCS) showed lava flows pouring down its side and a large plume of fiery smoke above the summit.

Authorities on Sunday upgraded the alert level at the Mayon volcano in the southern part of Luzon to “level 3” after observing steam eruptions and a bright lava glow.