@guardian: Authorities in Indonesia have issued a tsunami alert after Mount Ruang erupted five times in two days, spewing a column of smoke more than 2km into the sky. Officials worry that part of the stratovolcano in the province of North Sulawesi could collapse into the sea and cause a tsunami, as happened in 1871. Authorities have been rushing to evacuate 11,000 residents from nearby areas, including the remote island of Tagulandang, home to about 20,000 people. Volcanic eruptions and earthquakes occur frequently in Indonesia due to its position on the Pacific’s Ring of Fire – an arc where tectonic plates collide – which stretches from Japan through south-east Asia and across the Pacific basin. #indonesia #volcano #eruption