Mount Semeru, located on the border of Lumajang and Malang regencies, East Java, has once again shown high volcanic activity. On Thursday (2/7/2026) evening, the highest volcano on the island of Java was reported to have erupted, accompanied by pyroclastic flows.
Liswanto, an officer at the Mount Semeru Observation Post, confirmed that the eruption occurred at precisely 16:37 WIB. A column of volcanic ash was observed rising 1,500 meters above the summit, reaching 5,176 meters above sea level. The white-to-gray ash of moderate intensity moved toward the southeast.
Based on seismogram data, the eruption recorded a maximum amplitude of 22 millimeters with a duration of 6 minutes and 40 seconds. Pyroclastic flows were observed traveling 4 kilometers toward the Besuk Kobokan riverbed. As of the time of reporting, Semeru's volcanic activity status remains at Level III (Alert).
The Center for Volcanology and Geological Hazard Mitigation (PVMBG) issued strict instructions for residents around the slopes. The public is strictly prohibited from conducting any activities in the southeastern sector along Besuk Kobokan within a 13-kilometer radius from the summit. Additionally, activities are prohibited within 500 meters from the riverbanks of Besuk Kobokan due to the risk of expanding pyroclastic flows and lahar flows.
Furthermore, authorities have established a 5-kilometer radius danger zone from the crater to avoid the hazard of incandescent rock falls. Residents living along the river basins originating from the summit—namely Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat—are urged to exercise extra vigilance against secondary hazards such as lava flows and cold lahar flows.
