Indonesia: Indonesian authorities evacuated more than 900 people and rescued 170 climbers who were stranded after Mount Semeru erupted on Wednesday, sending towering ash clouds and dangerous pyroclastic flows down its slopes. The alert level on the volcano, the tallest on Java island, remains at its highest as activity continues.
The climbers had been stuck overnight at a lakeside campground about 6.4 kilometres from the crater. On Thursday, officials confirmed that all were being guided down safely. Septi Wardhani from the Semeru national park said the situation was under control and that the climbers and their guides were unharmed.
Semeru erupted 10 times on Wednesday, pushing plumes of ash more than 5.6 kilometres into the sky and hurling lava and rocks as far as 13 kilometres down its slopes. The eruption reduced visibility in surrounding areas and prompted aviation warnings as ash drifted across parts of East Java.
East Java’s rescue agency deployed dozens of personnel to help with the evacuation. At least 956 residents living near the volcano were moved to temporary shelters, including schools, mosques, and government buildings. Officials are also checking remote areas to ensure no one remains trapped.
Pyroclastic flow from Semeru about an hour ago.
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Credit: CCTV Semeru pic.twitter.com/aVV9ji0w2D
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Pyroclastic flows, the fast-moving clouds of hot ash and gas that pose the greatest danger, continued to be recorded on Thursday, reaching up to seven kilometres from the summit. Authorities urged people to stay at least 2.5 kilometres away from the crater as volcanic activity remains ongoing.
Mount Semeru, also known as Mahameru, rises 3,676 metres above sea level and is one of Indonesia’s most active volcanoes. Its last major eruption in December 2021 killed at least 51 people and blanketed nearby villages in ash. Over the past two centuries, Semeru has erupted repeatedly, with especially lethal events during the rainy season when volcanic debris can mix with water and cause destructive mudflows.
Semeru sits within Indonesia’s Pacific Ring of Fire, a vast belt of seismic activity where tectonic plates meet, creating frequent earthquakes and eruptions. With around 130 active volcanoes, Indonesia faces constant risks, and authorities are urging communities around Semeru to remain vigilant as the situation develops.
For now, emergency teams continue to monitor the mountain closely, ensuring that those who live and travel near one of the country’s most volatile peaks stay out of harm’s way.
