Mount Mahameru Eruption in Indonesia Triggers Evacuations

The nation's Semeru volcano, the tallest summit on the island of Java, has exploded, covering several villages with falling ash, leading to evacuations and causing officials to elevate the warning to the highest level.

The mountain in the province of East Java unleashed blistering plumes of fiery ash and a combination of stone, molten rock, and gases that moved up to 4 miles down its slopes multiple times from midday to evening, while a dense plume of hot clouds rose 2km into the air, as stated by the nation's geological authority.

The eruptions that unfolded throughout the day compelled authorities to increase the volcano’s alert level on two occasions, from the third-highest level to the highest, the authority said. No casualties have been announced.

Over three hundred inhabitants in the three communities most at risk in the district of Lumajang were evacuated to government shelters, as mentioned by a spokesperson for the national emergency management body.

He said that increased activity of the volcano on Wednesday afternoon led authorities to expand the hazard area to 8km from the summit. People were urged to keep away from an area along the Kobokan River, which is the path of the lava flow, as searing gas flowed down the volcano's sides.

Footage on online platforms showed a thick plume of ash moving through a wooded ravine to a river beneath a overpass. Residents, some with faces covered with volcanic dust and rain, fled to temporary shelters or left for alternative secure locations.

Regional news outlets reported that authorities were struggling to save about 178 individuals stranded on the 3,676-metre mountain at the Ranu Kumbolo monitoring post. The party included 137 climbers, 15 carriers, seven escorts and six tourism officials, according to an official with the national park.

“They are currently safe at Ranu Kumbolo monitoring post,” a spokesperson said in a video statement. He said the station was situated 4.5km from the summit on the northern slope of the mountain, which is not in the path of the hot cloud flow that was seen traveling to the southeast direction. Bad weather and rain required the team to spend the night there, he explained.

The volcano, also known as Mahameru, has erupted numerous times in the last two centuries. Still, as is the case with many of the 129 live volcanoes in the archipelago, thousands of people continue to live on its productive highlands.

Semeru’s previous significant explosion was in December 2021, when 51 people were killed and several hundred more were burned and villages were buried in thick mud. The eruption forced the evacuation of more than 10,000 people from their homes.

The country, an archipelago of over 280 million people, is located along the Pacific “ring of fire”, a horseshoe-shaped series of fault lines, and is susceptible to earthquakes and volcanic activity.