Mount Mahameru Outburst in the Southeast Asian nation Triggers Evacuations

The nation's Mount Semeru, the tallest summit on Java island, has erupted, covering several villages with volcanic ash, prompting evacuations and leading authorities to raise the alert to the highest level.

The volcano in East Java province unleashed blistering plumes of fiery ash and a combination of stone, molten rock, and gases that travelled up to 4 miles down its slopes multiple times from noon to evening, while a thick column of fiery clouds rose 2km into the sky, according to Indonesia’s Geology Agency.

The outbursts that occurred throughout the day forced officials to increase the mountain's warning status twice, from the level three to the highest, the agency said. No casualties have been announced.

Over three hundred residents in the three villages most endangered in the area of Lumajang region were relocated to government shelters, according to a representative for the national disaster mitigation agency.

He said that increased activity of the volcano on Wednesday afternoon led authorities to expand the hazard area to 8km from the summit. Residents were advised to stay clear from an area along the Besuk Kobokan River, which is the route of the lava flow, as scorching gases flowed down Semeru’s slopes.

Videos on social media showed a thick plume of volcanic dust moving through a forested valley to a waterway beneath a overpass. Residents, some with faces covered with ash and water, escaped to makeshift refuges or left for alternative secure locations.

Regional news outlets reported that emergency teams were facing challenges to save about 178 individuals trapped on the 3,676-metre peak at the Ranu Kumbolo monitoring post. The party included 137 climbers, 15 carriers, seven guides and six tourism officials, according to an official with the national park.

“They are currently safe at Ranu Kumbolo monitoring post,” a spokesperson stated in a recorded message. He noted the station was situated 4.5km from the crater on the north side of the volcano, which is outside the trajectory of the fiery cloud movement that was seen moving to the south-southeast. Bad weather and precipitation required the team to spend the night there, he explained.

The volcano, also called Great Mountain, has erupted numerous times in the past 200 years. However, as is the situation with numerous of the 129 live volcanoes in Indonesia, tens of thousands of people still to live on its productive highlands.

Semeru’s previous significant explosion was in December 2021, when 51 people were killed and hundreds others were injured and villages were buried in layers of mud. The event forced the evacuation of over ten thousand people from their houses.

The country, an island chain of over 280 million inhabitants, sits along the Pacific seismic belt, a horseshoe-shaped series of tectonic boundaries, and is susceptible to earthquakes and volcanism.