Volcano Semeru Eruption in Indonesia Prompts Emergency Relocations

Indonesia's Semeru volcano, the highest peak on Java island, has exploded, blanketing multiple communities with falling ash, prompting evacuations and leading authorities to raise the warning to the highest level.

The volcano in the province of East Java unleashed searing clouds of hot ash and a mixture of stone, molten rock, and gases that travelled up to 4 miles down its sides multiple times from noon to evening, while a dense plume of fiery clouds rose 1.2 miles into the air, according to the nation's geological authority.

The outbursts that occurred throughout the day compelled authorities to raise the mountain's warning status twice, from the level three to the highest, the authority reported. No casualties have been reported.

More than 300 inhabitants in the three villages most endangered in the district of Lumajang region were relocated to official safe havens, according to a spokesperson for the national emergency management body.

He said that increased activity of the mountain on Wednesday afternoon led officials to expand the hazard area to 8km from the summit. Residents were advised to stay clear from an area along the Besuk Kobokan River, which is the path of the molten rock stream, as scorching gases moved down Semeru’s slopes.

Videos on social media showed a dense cloud of ash moving through a forested valley to a waterway beneath a overpass. Locals, some with faces covered with volcanic dust and rain, fled to makeshift refuges or left for other safe areas.

Local media reported that emergency teams were facing challenges to rescue about 178 people stranded on the 12,060-foot mountain at the Ranu Kumbolo observation station. The group included 137 climbers, 15 porters, 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 noted the post was situated 2.8 miles from the summit on the northern slope of the volcano, which is not in the path of the hot cloud flow that was seen traveling to the southeast direction. Inclement conditions and precipitation forced the group to spend the night there, he explained.

The volcano, also called Mahameru, has burst many occasions in the last two centuries. However, as is the situation with many of the 129 live volcanoes in Indonesia, thousands of people continue to live on its productive highlands.

Semeru’s last major eruption was in late 2021, when 51 individuals were killed and hundreds others were injured and settlements were submerged in thick mud. The event forced the relocation of more than 10,000 residents from their houses.

Indonesia, an archipelago of more than 280 million inhabitants, sits along the Pacific “ring of fire”, a curved series of fault lines, and is susceptible to seismic events and volcanic activity.