FLORES ISLAND, Indonesia – Mount Lewotobi Laki-laki on Indonesia's southeastern Flores Island erupted on June 18, 2025, spewing a colossal ash plume up to 10,000 meters (approximately 32,800 feet) into the atmosphere. The significant volcanic activity led to the cancellation of dozens of flights from Bali's I Gusti Ngurah Rai International Airport and other regional air hubs, causing widespread travel disruptions.

The Indonesian Geological Agency reported a marked increase in the volcano's activity, with over 50 events recorded within two hours on June 18, a stark contrast to its usual 8-10 daily occurrences. This surge prompted authorities to elevate the eruption alert to the highest level, Level 4, and expand the exclusion zone around the crater to 8 kilometers (about 5 miles). Volcanic ash formed a distinct mushroom-shaped cloud, visible from cities up to 150 kilometers away from the mountain.

The ash cloud, posing a serious risk to aircraft engines, forced the cancellation of at least 87 international and domestic flights at Bali's Ngurah Rai Airport. Affected international routes included those connecting Bali to cities in Australia, Malaysia, India, and China, with airlines such as Jetstar, Virgin Australia, and Air New Zealand confirming disruptions. Flights to and from Labuan Bajo International Airport on Flores Island were also impacted. While no casualties have been reported from this latest eruption, local officials initiated evacuations for residents in villages near the volcano, including Boru, Hewa, Watobuku, Nurabelen, and Nileknoheng.

Mount Lewotobi Laki-laki, standing at 1,584 meters (5,197 feet) and forming a twin volcanic complex with Mount Lewotobi Perempuan, has a history of intermittent eruptions. Notably, a series of eruptions in November 2024 resulted in the deaths of at least 10 people and injured dozens. Further significant eruptions occurred in March and May 2025, also causing air travel disruptions and displacement of local populations.

Indonesia, an archipelago nation, is home to approximately 120 active volcanoes, making it one of the most volcanically active countries globally. Its geographical location along the "Ring of Fire"—a horseshoe-shaped series of seismic fault lines encircling the Pacific Basin—contributes to frequent volcanic eruptions and seismic activity. The National Disaster Management Agency continues to monitor the situation closely, advising vigilance for potential mudflows due to heavy rainfall mixing with volcanic ash.