Volcano Mahameru Outburst in Indonesia Triggers Evacuations

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

The volcano in the province of East Java released searing clouds of fiery ash and a combination of stone, molten rock, and gases that travelled up to 7km down its sides several times from midday to dusk, while a dense plume of hot clouds rose 2km into the sky, according to Indonesia’s Geology Agency.

The outbursts that unfolded throughout the day compelled authorities to increase the mountain's warning status on two occasions, from the level three to the top level, the authority said. No casualties have been announced.

Over three hundred residents in the three villages most at risk in the district of Lumajang region were relocated to government shelters, according to a spokesperson for the national disaster mitigation agency.

He said that heightened volcanic movements of the volcano on Wednesday afternoon prompted authorities to expand the danger zone to 8km from the summit. People were urged to keep away from an area along the Besuk Kobokan River, which is the path of the molten rock stream, as scorching gases flowed down Semeru’s slopes.

Videos on online platforms displayed a thick plume of ash moving through a wooded ravine to a waterway beneath a overpass. Residents, some with faces smeared with volcanic dust and rain, escaped to temporary shelters or left for other safe areas.

Local media reported that authorities were facing challenges to rescue about 178 individuals trapped on the 3,676-metre mountain at the Ranu Kumbolo observation station. The party comprised 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,” an official stated in a video statement. He said the post was situated 4.5km from the summit on the north side of the mountain, which is outside the trajectory of the hot cloud flow that was observed traveling to the south-southeast. Bad weather and rain required the group to remain overnight there, he added.

The volcano, also known as Great Mountain, has burst numerous times in the past 200 years. Still, as is the case with numerous of the 129 active volcanoes in Indonesia, tens of thousands of people continue to reside on its fertile slopes.

The mountain's last major eruption was in late 2021, when 51 individuals were lost their lives and hundreds more were injured and villages were buried in layers of mud. The event led to the relocation of more than 10,000 residents from their homes.

Indonesia, an island chain of more than 280 million people, is located along the Pacific seismic belt, a curved series of fault lines, and is susceptible to earthquakes and volcanic activity.