Mount Semeru Eruption in Indonesia Prompts Evacuations

The nation's Mount Semeru, the tallest summit on Java island, has erupted, covering multiple communities with falling ash, leading to evacuations and causing officials to elevate the warning to the highest level.

The volcano in East Java province released blistering plumes of fiery ash and a combination of rock, lava and gas that travelled up to 7km down its slopes several times from midday to dusk, while a thick column of fiery clouds rose 2km into the sky, as stated by the nation's geological authority.

The eruptions that occurred throughout the day compelled officials to increase the volcano’s alert level twice, from the level three to the highest, the agency reported. No deaths or injuries have been reported.

More than 300 residents in the three villages most at risk in the area of Lumajang were relocated to government shelters, according to a spokesperson for the national disaster mitigation agency.

He stated that heightened volcanic movements of the mountain on the afternoon of Wednesday led officials to expand the danger zone to 8km from the crater. People were urged to keep away from an zone along the Besuk Kobokan River, which is the path of the lava flow, as scorching gases flowed down the volcano's sides.

Videos on social media showed a thick plume of volcanic dust sweeping through a forested valley to a waterway beneath a overpass. Residents, some with faces smeared with volcanic dust and water, fled to temporary shelters or left for alternative secure locations.

Regional news outlets reported that emergency teams were struggling to rescue about 178 people stranded on the 3,676-metre peak at the Ranu Kumbolo monitoring post. The party comprised 137 hikers, 15 carriers, seven escorts and six travel representatives, according to an spokesperson with the national park.

“They remain secure at Ranu Kumbolo monitoring post,” a spokesperson said in a video statement. He said the station was situated 2.8 miles from the crater 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 required the group to remain overnight there, he added.

Semeru, also known as Great Mountain, has erupted many occasions in the last two centuries. However, as is the case with many of the 129 active 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 individuals were lost their lives and hundreds more were burned and settlements were buried in thick mud. The event led to the evacuation of over ten thousand people from their homes.

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