Mount Semeru Eruption in Indonesia Triggers Evacuations

Indonesia's Mount Semeru, the highest peak on Java island, has exploded, covering multiple communities with volcanic ash, leading to evacuations and leading authorities to raise the alert to the maximum level.

The volcano in East Java province unleashed searing clouds of hot ash and a mixture of rock, lava and gas that travelled up to 7km down its sides several times from noon to dusk, while a dense plume of hot clouds rose 2km into the sky, according to Indonesia’s Geology Agency.

The outbursts that unfolded throughout the day compelled officials to increase the mountain's warning status on two occasions, from the third-highest level to the top level, the agency reported. No deaths or injuries have been announced.

Over three hundred inhabitants in the three villages most at risk in the area of Lumajang were relocated to official safe havens, as mentioned by a spokesperson for the national disaster mitigation agency.

He stated that increased activity of the mountain on Wednesday afternoon led authorities to expand the hazard area to 5 miles from the summit. People were advised to stay clear 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.

Footage on social media displayed a dense cloud of ash moving through a forested valley to a waterway beneath a overpass. Residents, some with faces smeared with volcanic dust and water, escaped to temporary shelters or departed for alternative secure locations.

Regional news outlets indicated that authorities were struggling to rescue about 178 people stranded on the 3,676-metre peak at the Ranu Kumbolo observation station. The group included 137 hikers, 15 carriers, seven escorts and six tourism officials, according to an official with the protected area.

“They are currently safe at the Ranu Kumbolo station,” a spokesperson said in a video statement. He noted the post was located 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 observed moving to the south-southeast. Inclement conditions and rain required the team to remain overnight there, he explained.

Semeru, also known as Great Mountain, has erupted numerous times in the last two centuries. Still, as is the situation with many of the 129 active volcanoes in Indonesia, thousands of residents still to reside on its productive highlands.

Semeru’s last major eruption was in December 2021, when 51 individuals were lost their lives and several hundred more were injured and villages were submerged in layers of mud. The eruption led to the evacuation of more than 10,000 people from their homes.

The country, an archipelago of more than 280 million inhabitants, sits along the Pacific seismic belt, a horseshoe-shaped series of fault lines, and is susceptible to seismic events and volcanic activity.