The Semeru volcano on Java Island in Indonesia has erupted, sending an ash column into the air up to 1.5 kilometers high, prompting authorities to warn residents to stay away from the area. The Indonesian Disaster Mitigation Agency cautioned people against engaging in any activities within 5 kilometers of the eruption center and urged them to remain at least 500 meters away from riverbanks due to the risk of lava flows. The Japan Meteorological Agency stated it is monitoring the likelihood of tsunami waves in the area following the volcano's eruption, as reported by Japan's NHK. Indonesian authorities have raised the alert level for the volcanic eruption to level four, the highest level.