Mount Mahameru Eruption in the Southeast Asian nation Triggers Evacuations

Indonesia's Mount Semeru, the tallest summit on the island of Java, has exploded, blanketing multiple communities with volcanic ash, leading to evacuations and causing officials to elevate the alert to the highest level.

The mountain 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 noon to dusk, while a thick column of hot 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 on two occasions, from the level three to the highest, the authority reported. No casualties have been announced.

More than 300 residents in the three communities most endangered in the district of Lumajang region were relocated to government shelters, as mentioned by a spokesperson for the national emergency management body.

He stated that increased activity of the volcano on the afternoon of Wednesday led authorities to widen the hazard area to 5 miles from the summit. Residents were advised to stay clear from an zone along the Kobokan River, which is the route of the lava flow, as scorching gases flowed down Semeru’s slopes.

Footage on online platforms displayed a dense cloud of ash moving through a wooded ravine to a river beneath a overpass. Residents, some with faces covered with ash and rain, escaped to makeshift refuges or left for alternative secure locations.

Local media reported that authorities were struggling to rescue about 178 people stranded on the 3,676-metre mountain at the Ranu Kumbolo observation station. The party comprised 137 climbers, 15 carriers, seven escorts and six tourism officials, according to an official with the protected area.

“They remain secure at the Ranu Kumbolo station,” a spokesperson said in a video statement. He noted the station was located 4.5km from the summit on the northern slope of the volcano, which is not in the path of the fiery cloud movement that was seen traveling to the southeast direction. Inclement conditions and precipitation forced the group to spend the night there, he added.

Semeru, also called Great Mountain, has erupted numerous times in the past 200 years. Still, as is the case with numerous of the 129 live volcanoes in the archipelago, tens of thousands of people still to reside on its fertile slopes.

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

Indonesia, an island chain of over 280 million people, is located along the Pacific seismic belt, a horseshoe-shaped series of fault lines, and is prone to earthquakes and volcanism.