More than 11,000 people have left their homes near Mount Agung after Indonesian authorities raised the alert for the volcano on the resort island of Bali to one notch below the highest level, the Deutsch Presse-Agentur, DPA, has reported.
Mount Agung has shown increased activity since last week, prompting the government to warn people to stay away from an exclusion zone of 7.5 kilometres from the volcano's crater.
"More than 11,000 residents around Mount Agung have sought refuge," said Sutopo Nugroho, a spokesman for the National Disaster Management Agency, on Friday.
"Hundreds of harmonic tremors have been detected," he said.
The 3,030-metre Mount Agung last erupted in 1963-64, killing about 1,500 people.