A volcano in Indonesia's North Sulawesi province erupted Tuesday, but there were no casualties, an official said. No evacuation order was issued after the eruption of Mount Lokon in the Tomohon district, said Sutopo Nugroho, a spokesman for the National Disaster Management Agency. "The eruption was heard from the monitoring post 5 kilometers from the volcano, but it was too foggy to see," he said, adding that the volcano''s alert status remained at the second-highest level. Mount Lokon has erupted several times this year. A series of eruptions in July forced more than 5,000 people to flee to safer areas. Indonesia sits in the Pacific Ring of Fire, an area known for its frequent earthquakes and volcanic eruptions. The archipelago is home to at least 129 active volcanoes.