Indonesia’s highest volcano erupts as evacuations carried out on most densely populated island

Indonesia’s highest volcano erupted on Sunday, prompting evacuation orders and raising the country’s volcanic activity threat level to its highest after the release of searing gas clouds, rivers of lava and thick columns of ash spread over 4,000 feet into the sky.

Mount Semeru, a 12,060ft volcano, erupted after monsoon rains eroded its lava dome, leading to its collapse, said Abdul Muhari, spokesperson for the National Disaster Management Agency.

The volcano, located on Java, Indonesia’s most densely populated island, left several villages blanketed in ash and blocking out the sun as thick plumes of smoke spread over 4,000ft into the sky.

Gas and lava flowed down Semeru’s slopes, traveling toward a nearby river.

“Most roads have been closed since this morning and now it is raining volcanic ash and it has covered the view of the mountain,” community volunteer Bayu Deny Alfianto was quoted as saying to Reuters by telephone from near the volcano.

Authorities said no casualties have been reported so far and have warned residents to stay at a distance of 5km from the crater’s mouth.

They have also been warned to keep off the southeastern sector area along the Besuk Kobokan river, located about 13km from the crater.

Mount Semeru releases volcanic materials during an eruption on Sunday (AP)
Mount Semeru releases volcanic materials during an eruption on Sunday (AP)

Joko Sambang, who heads the disaster management agency in Lumajang, East Java province, said hundreds of people have been moved to temporary shelters or left for other safe areas. Residents consisted mostly of woman, children and elders.

Japan’s public broadcaster NHK reported that the country’s Meteorology Agency was monitoring for the possibility of a tsunami there after the eruption, but later said that there was no tsunami impact.

Indonesia’s Center for Volcanology and Geological Hazard Mitigation, PVMBG chief Hendra Gunawan, said a bigger volume of magma could have built up compared with previous eruptions of the volcano, in 2021 and 2020, which could mean greater danger for a bigger area.

“Semeru’s hot clouds could reach further and at a distance where there are many residences,” he was quoted as saying.

Semeru, also known as Mahameru, has erupted numerous times in the last 200 years. Its last major eruption was in December 2021 which left 51 people dead and several hundreds injured with serious burns.

More than 10,000 villagers were then evacuated.

Indonesia is located on the “Pacific Ring of Fire” and has 142 volcanoes. The country has the largest global population living in close range to a volcano.

About 8.6 million of Indonesians live within the 10km range of a volcano.

Additional reporting by agencies