Mount Mahameru Outburst in the Southeast Asian nation Triggers Evacuations

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

The volcano in East Java province unleashed searing clouds of hot ash and a mixture of rock, lava and gas that moved up to 7km down its slopes multiple times from midday to dusk, while a dense plume of fiery clouds rose 1.2 miles into the air, as stated by Indonesia’s Geology Agency.

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

Over three hundred inhabitants in the three communities most at risk in the district of Lumajang region were evacuated to official safe havens, as mentioned by a representative for the national disaster mitigation agency.

He said that increased activity of the mountain on Wednesday afternoon led officials to widen the danger zone to 5 miles from the summit. People were advised to keep away from an area along the Kobokan River, which is the route of the molten rock stream, as searing gas flowed down Semeru’s slopes.

Videos on social media displayed a thick plume of ash moving through a forested valley to a river beneath a bridge. Locals, some with faces smeared with ash and rain, escaped to makeshift refuges or departed for other safe areas.

Regional news outlets indicated that authorities were struggling to save about 178 people stranded on the 3,676-metre mountain at the Ranu Kumbolo monitoring post. The party included 137 hikers, 15 carriers, seven escorts and six tourism officials, according to an spokesperson with the protected area.

“They remain secure at the Ranu Kumbolo station,” a spokesperson stated in a video statement. He said the post was situated 4.5km from the summit on the north side of the volcano, which is outside the trajectory of the hot cloud flow that was seen traveling to the south-southeast. Bad weather and rain forced the group to remain overnight there, he added.

Semeru, also known as Great Mountain, has erupted many occasions in the last two centuries. Still, as is the situation with many of the 129 active volcanoes in the archipelago, tens of thousands of residents still to reside on its fertile slopes.

Semeru’s last major eruption was in December 2021, when 51 people were lost their lives and hundreds more were burned and villages were buried in thick mud. The event led to the relocation of more than 10,000 residents from their houses.

The country, an island chain of more than 280 million inhabitants, sits along the Pacific “ring of fire”, a horseshoe-shaped series of tectonic boundaries, and is susceptible to earthquakes and volcanic activity.