Indonesia issues tsunami alert as volcano erupts

More than 800 people evacuated from Mount Ruang as alert level raised to four - highest in four-tier system

Authorities in Indonesia have issued a tsunami alert after a volcano erupted several times in the country's southernmost region, spewing a column of smoke more than a mile into the sky and forcing hundreds of people to be evacuated from their homes.

Mount Ruang, a stratovolcano in North Sulawesi province, first erupted at 9.45pm local time on Tuesday and then four times on Wednesday, Indonesia's volcanology agency said.