Mount Mahameru Outburst in Indonesia Prompts Evacuations

The nation's Mount Semeru, the highest peak on Java island, has erupted, blanketing multiple communities with volcanic ash, prompting evacuations and causing officials to elevate the warning to the maximum level.

The mountain in the province of East Java released searing clouds of fiery ash and a combination of rock, lava and gas that moved up to 7km down its slopes multiple times from noon to dusk, while a thick column of fiery clouds rose 1.2 miles into the air, according to the nation's geological authority.

The eruptions that occurred throughout the day forced authorities to increase the volcano’s alert level twice, from the third-highest level to the top level, the authority said. No casualties have been reported.

Over three hundred 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 emergency management body.

He said that increased activity of the volcano on the afternoon of Wednesday prompted officials to expand the hazard area to 5 miles from the summit. Residents were advised to keep away from an area along the Kobokan River, which is the path of the lava flow, as searing gas moved down Semeru’s slopes.

Footage on online platforms showed a thick plume of ash moving through a forested valley to a river beneath a bridge. Residents, some with faces smeared with volcanic dust and water, escaped to temporary shelters or departed for other safe areas.

Regional news outlets reported that emergency teams were struggling to rescue about 178 people trapped on the 3,676-metre mountain at the Ranu Kumbolo observation station. The group comprised 137 hikers, 15 carriers, seven guides and six travel representatives, according to an spokesperson with the national park.

“They remain secure at the Ranu Kumbolo station,” a spokesperson said in a recorded message. He said the post was situated 4.5km from the crater on the northern slope of the volcano, which is not in the path of the fiery cloud movement that was seen moving to the southeast direction. Bad weather and rain forced the group to remain overnight there, he added.

Semeru, also called Mahameru, has erupted many occasions in the last two centuries. However, as is the case with numerous of the 129 active volcanoes in Indonesia, thousands of residents continue to live on its productive highlands.

The mountain's previous significant explosion was in late 2021, when 51 people were lost their lives and several hundred others 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, is located along the Pacific “ring of fire”, a horseshoe-shaped series of tectonic boundaries, and is susceptible to earthquakes and volcanic activity.