Mount Mahameru Eruption in Indonesia Prompts Evacuations

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

The volcano in the province of East Java released blistering plumes of hot ash and a combination of rock, lava and gas that moved up to 7km down its slopes multiple times from midday to dusk, while a dense plume of hot clouds rose 1.2 miles into the sky, according to Indonesia’s Geology Agency.

The eruptions that occurred throughout the day forced authorities to increase the mountain's warning status twice, from the third-highest level to the highest, the agency reported. No casualties have been announced.

More than 300 residents in the three villages most at risk in the area of Lumajang region were relocated to government shelters, as mentioned by a representative for the national disaster mitigation agency.

He said that heightened volcanic movements of the mountain on Wednesday afternoon led officials to expand the hazard area to 8km from the crater. Residents were urged to stay clear from an zone along the Besuk Kobokan River, which is the route of the lava flow, as searing gas flowed down Semeru’s slopes.

Footage on social media displayed a dense cloud of ash moving through a wooded ravine to a waterway beneath a bridge. Locals, some with faces covered with volcanic dust and rain, escaped to temporary shelters or left for other safe areas.

Local media indicated that authorities were struggling to save about 178 individuals stranded on the 3,676-metre peak at the Ranu Kumbolo monitoring post. The party included 137 hikers, 15 porters, seven escorts and six travel representatives, according to an official with the national park.

“They are currently safe at Ranu Kumbolo monitoring post,” an official said in a recorded message. He said the post was located 4.5km from the crater on the north side of the mountain, which is outside the trajectory of the hot cloud flow that was seen traveling to the south-southeast. Inclement conditions and rain forced the team to spend the night there, he added.

Semeru, also known as Great Mountain, has burst many occasions in the last two centuries. However, as is the case with numerous of the 129 live volcanoes in the archipelago, tens of thousands of residents still to live on its fertile slopes.

Semeru’s last major eruption was in late 2021, when 51 individuals were lost their lives and hundreds more were burned and settlements were buried in layers of mud. The eruption led to the evacuation of over ten thousand people from their houses.

The country, an island chain of over 280 million inhabitants, is located along the Pacific “ring of fire”, a curved series of fault lines, and is susceptible to seismic events and volcanism.