Mount Mahameru Eruption in Indonesia Triggers Evacuations

Indonesia's Semeru volcano, the highest peak on Java island, has exploded, covering several villages with volcanic ash, prompting evacuations and leading authorities to raise the alert to the highest level.

The volcano in East Java province released searing clouds of hot ash and a mixture of stone, molten rock, and gases that moved up to 7km down its sides several times from noon to dusk, while a dense plume of fiery clouds rose 2km 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 on two occasions, from the third-highest level to the top level, the agency reported. No casualties have been announced.

Over three hundred inhabitants in the three villages most at risk in the district of Lumajang region were relocated to official safe havens, according to a representative for the national disaster mitigation agency.

He stated that heightened volcanic movements of the mountain on the afternoon of Wednesday led 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 lava flow, as scorching gases moved down the volcano's sides.

Videos on social media displayed a dense cloud of volcanic dust sweeping through a forested valley to a waterway beneath a overpass. Locals, some with faces smeared with ash and water, fled to temporary shelters or left for alternative secure locations.

Local media indicated that authorities were facing challenges to rescue about 178 individuals stranded on the 12,060-foot peak at the Ranu Kumbolo monitoring post. The group comprised 137 hikers, 15 carriers, seven guides and six travel representatives, according to an spokesperson with the protected area.

“They are currently safe at Ranu Kumbolo monitoring post,” an official said in a video statement. He said the post was situated 4.5km from the summit on the north side of the volcano, which is not in the path of the hot cloud flow that was observed traveling to the south-southeast. Bad weather and precipitation required the team to spend the night there, he explained.

The volcano, also known as Great Mountain, has burst numerous times in the past 200 years. However, as is the case with many of the 129 live volcanoes in Indonesia, thousands of residents still to reside on its fertile slopes.

Semeru’s last major eruption was in late 2021, when 51 people were lost their lives and several hundred more were burned and settlements were submerged in layers of mud. The event led to the relocation of over ten thousand residents from their houses.

Indonesia, an island chain of over 280 million people, sits along the Pacific “ring of fire”, a horseshoe-shaped series of fault lines, and is susceptible to seismic events and volcanism.