Mount Semeru Erupts, Sends 6,500‑ft Ash Plume; 300+ Evacuated as Red Aviation Alert Issued

Indonesia's Mount Semeru erupted Wednesday afternoon, sending volcanic ash columns up to 6,500 feet (about 2,000 meters) into the sky and prompting the evacuation of more than 300 people. The eruption created hazardous conditions for nearby communities and posed a potential threat to regional air traffic.

The event occurred at about 4 p.m. local time on East Java's highest peak, which rises to 12,060 feet (3,675 meters). Australia's Bureau of Meteorology Volcanic Ash Advisory Center in Darwin issued a red aviation alert, signaling a material hazard to aircraft in the affected airspace.

Airlines operating in the region, including Qantas, Jetstar and Virgin Australia, said they were monitoring ash dispersion closely. At the time of reporting they had not cancelled scheduled services but confirmed they would contact customers if flight plans were changed for safety reasons.

Indonesian authorities raised Mount Semeru's status to Level 4, the highest alert, indicating an ongoing eruption and elevated danger to nearby areas. Officials warned the volcano can eject pyroclastic material as far as 5 miles (about 8 kilometers) from the summit and imposed a 12-mile (approximately 19 kilometers) exclusion zone to reduce the risk to residents from lava flows and hot ash clouds.

Indonesia records frequent volcanic activity and is home to 101 volcanoes, according to the Smithsonian Institution's Global Volcanism Program. Local authorities urged people in affected areas to follow evacuation orders, avoid the exclusion zone, and stay alert to further updates from emergency services and aviation authorities.

Safety note: Volcanic ash can damage aircraft engines and reduce visibility. Travelers should check with their airline for the latest flight information and heed instructions from local officials.