Monday’s eruption was the second time in a week the stratovolcano Mount Lokon erupted, prompting officials to place nearby Tomohon City on the third highest alert level.
Mt. Lokon, part of a twin volcano system with adjacent Mount Empung, is among the most active volcanoes on the island, which is part on an archipelago in northeastern Indonesia along the Celebes Sea.
Locals heard a loud boom in Tomohon City, but did not seem fazed by the eruption, which has come to be a regular occurrence. The 5,540-foot-tall volcano has been active since July 2011, sometimes erupting two to three times in a week.
Monday’s eruption sent ash spewing across the south and southeastern parts of Tomohon City, three miles away from the volcanic crater.
Local officials warned residents not to go within a mile of the crater, but evacuation has not been ordered.
“Mount Lokon is still sending a plume of ash into the sky. Face mask distribution, coordinated by the BPBD Tomohon City, is underway,” said Hoyke Makarawung, Regional Disaster Mitigation Agency (BPBD) chapter head.
The archipelago nation Indonesia’s geography is dominated by volcanoes due to its location along two subduction zones between the Eurasian plate and the Indo-Austrailan plate. As of 2012 there were 127 active volcanoes in the country, including Mount Tambora, which in 1815 erupted with a force of VEI-7, one of the most powerful volcanic events in recorded history.