Mount Mahameru Eruption in Indonesia Prompts Emergency Relocations

Indonesia's Mount Semeru, the highest peak on the island of Java, has exploded, blanketing multiple communities with falling ash, prompting evacuations and leading authorities to raise the warning to the maximum level.

The volcano in the province of East Java released blistering plumes of hot ash and a mixture of rock, lava and gas that travelled up to 7km down its slopes multiple times from midday to evening, while a thick column of fiery clouds rose 1.2 miles into the sky, as stated by Indonesia’s Geology Agency.

The eruptions that occurred throughout the day forced officials to increase the mountain's warning status twice, from the third-highest level to the top level, the agency said. No deaths or injuries have been reported.

Over three hundred inhabitants in the three villages most at risk in the area of Lumajang were evacuated to official safe havens, according to a representative for the national disaster mitigation agency.

He said that heightened volcanic movements of the mountain on Wednesday afternoon led officials to widen the hazard area to 8km from the summit. People were urged to keep away from an zone along the Kobokan River, which is the path of the molten rock stream, as scorching gases moved down Semeru’s slopes.

Videos on social media displayed a dense cloud of volcanic dust sweeping through a wooded ravine to a river beneath a bridge. Residents, some with faces covered with volcanic dust and water, escaped to temporary shelters or departed for other safe areas.

Local media reported that emergency teams were facing challenges to save about 178 individuals trapped on the 12,060-foot mountain at the Ranu Kumbolo monitoring post. The group comprised 137 hikers, 15 carriers, seven guides and six tourism officials, according to an spokesperson with the protected area.

“They are currently safe at Ranu Kumbolo monitoring post,” a spokesperson said in a recorded message. He said the post was situated 4.5km from the crater on the north side of the mountain, which is not in the path of the fiery cloud movement that was observed moving to the south-southeast. Bad weather and precipitation required the team to spend the night there, he explained.

Semeru, also called Great Mountain, has burst numerous times in the past 200 years. However, as is the situation with numerous of the 129 active volcanoes in the archipelago, thousands of residents still to reside on its productive highlands.

Semeru’s last major eruption was in late 2021, when 51 people were killed and hundreds others were injured and settlements were submerged in layers of mud. The eruption forced the evacuation of over ten thousand people from their houses.

Indonesia, an archipelago of more than 280 million inhabitants, sits along the Pacific seismic belt, a curved series of fault lines, and is prone to seismic events and volcanic activity.