A volcano that has been spewing lava and clouds of searing gas high into the air let out a new, powerful burst, sending panicked villagers streaming down the sides of the mountain.
One person was injured, said Ludianto, head of the search and rescue team, a man who fell as he was fleeing. The victim suffered only cuts and bruises, however, and no burns as earlier reported.
Mount Karangetang on Siau - part of the Sulawesi island chain - started spitting clouds of gas and lava up to 1,900 feet (600 meters) on Friday, said volcanologist Surono.
Early on Monday, hot ash tumbled down its slopes triggering fresh panic.
Nearly 600 people living along Karangetang's slopes have been evacuated, said Tonny Supit, the district chief.
Indonesia lies on the Pacific "Ring of Fire," an arc of volcanos and fault lines encircling the Pacific Basin.
The 5,853-foot (1,784-meter) mountain is one of about 129 active volcanoes in Indonesia. It's last big eruption was in August, killing four people.
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