Indonesia’s Mount Semeru, the tallest volcano on Java island, erupted on Wednesday, prompting authorities to raise its alert level to the highest. The eruption sent ash plumes soaring up to 5.6 kilometers into the sky and unleashed fast-moving pyroclastic flows reaching seven kilometers from the summit. The country’s volcanology agency has urged residents to stay at least 2.5 kilometers away from the crater due to ongoing risks. Located on the Pacific 'Ring of Fire', Mount Semeru stands at 3,676 meters and is among Indonesia’s most active volcanoes. The region, densely populated and prone to seismic activity, faces potential threats to nearby communities, transport routes, and aviation. Semeru, also known as Mahameru, has a long history of eruptions, including a deadly one in 2021 that killed 62 people and buried several villages in ash. Indonesia, with nearly 130 active volcanoes, continues to monitor Semeru closely for further activity.