Mount Mahameru Outburst in the Southeast Asian nation Prompts Evacuations

The nation's Mount Semeru, the highest peak on Java island, has exploded, covering multiple communities with volcanic ash, leading to evacuations and causing officials to elevate the alert to the highest level.

The volcano in the province of East Java released blistering plumes of hot ash and a mixture of stone, molten rock, and gases that travelled up to 7km down its sides several times from midday to dusk, while a thick column of hot clouds rose 2km into the sky, as stated by Indonesia’s Geology Agency.

The eruptions that occurred throughout the day compelled officials to raise the volcano’s alert level twice, from the level three to the top level, the agency said. No casualties have been announced.

Over three hundred inhabitants in the three communities most endangered in the district of Lumajang were evacuated to official safe havens, according to a spokesperson for the national disaster mitigation agency.

He said that increased activity of the mountain on Wednesday afternoon led officials to expand the hazard area to 8km from the summit. People were advised to stay clear from an zone along the Besuk Kobokan River, which is the route of the lava flow, as searing gas moved down the volcano's sides.

Videos on social media displayed a dense cloud of ash moving through a forested valley to a river beneath a bridge. Locals, some with faces covered with ash and water, fled to temporary shelters or left for other safe areas.

Regional news outlets reported that authorities were facing challenges to rescue about 178 individuals stranded on the 3,676-metre mountain at the Ranu Kumbolo monitoring post. The party comprised 137 hikers, 15 carriers, seven guides and six travel representatives, according to an spokesperson with the protected area.

“They are currently safe at the Ranu Kumbolo station,” an official stated in a video statement. He said the station was located 2.8 miles from the summit on the northern slope of the volcano, which is outside the trajectory of the hot cloud flow that was seen moving to the south-southeast. Bad weather and precipitation required the team to remain overnight there, he added.

Semeru, also called Mahameru, has erupted numerous times in the last two centuries. Still, as is the situation with many of the 129 live volcanoes in Indonesia, tens of thousands of people still to reside on its fertile slopes.

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

Indonesia, an archipelago of more than 280 million people, is located along the Pacific “ring of fire”, a curved series of tectonic boundaries, and is prone to seismic events and volcanic activity.