Mount Lewotobi Laki-Laki, a 1,584-meter volcano on Indonesia’s Flores Island, erupted around 5:35 p.m. local time on Tuesday, sending a dense ash cloud 10,000 meters into the sky.

Indonesia’s Geology Agency described it as a powerful eruption with “dense, grey clouds.” The agency warned of possible lava flows if heavy rain follows and raised the volcano’s alert status to the highest level.

This eruption followed an unusual surge in volcanic activity — “fifty eruptions in two hours,” compared to the usual eight to ten.

Though no casualties or damage were reported, authorities urged residents and tourists to avoid the area. The ash could pose risks to flights, though it remained unclear if any were grounded.

Officials continue to monitor the situation closely as the region braces for more potential activity.