Updated

A volcano in central Indonesia spit lava and smoke high into the air early Friday, sending thousands of panicked residents racing down its fiery slopes. One woman died of a heart attack as she fled, but there were no immediate reports of other casualties.

Mount Lokon, located in northern Sulawesi province, unleashed its first powerful eruption at 10:46 p.m. Thursday, said Brian Rulrone, a disaster management agency official. That blast was followed by a second just after midnight and a third at 1:10 a.m. Friday.

Glowing lava cascaded from the mouth of the crater, setting trees ablaze along the western slope, said Ferry Rusmawan, an official at the nearest monitoring post, adding that activity remained high and another eruption appeared imminent.

The 5,741-foot (1,750-meter) mountain continued to rumble late Friday morning.

Soldiers and police helped rescuers evacuate residents living along the mountain's fertile slopes, said Jimmy Eman, the acting mayor in the nearby town of Tomohon, adding that the only victim so far was the 56-year-old woman who died of a heart attack.

More than 6,000 people were crammed into schools, churches and other temporary shelters.

"This is the largest eruption I've ever experienced," said Nelson Uada, who was among those evacuated overnight. "It was very scary. Glowing lava flowed like flames in the darkness and it sounded like we were in a war."

There were disruptions to air travel in the area.

Indonesia, a vast archipelago of 240 million people, is prone to earthquakes and volcanoes because it sits along the Pacific "Ring of Fire," a horseshoe-shaped string of faults that lines the Pacific Ocean.

Mount Lokon, which has been on high alert for nearly a week, is one of the country's 129 active volcanos.

Its last major eruption in 1991 killed a Swiss hiker and forced thousands of people to flee their homes.