Thousands of residents have left villages near an active volcano on Bali as seismic tremors rattled some areas and smoke rose above one of the world’s most popular tourist spots.

The alert status for Mount Agung in eastern Bali is at three, one level below the highest, and authorities warn tourists and residents to avoid camping or hiking within a 6km radius of the crater.

“Volcanic activity remains high and there are indications of magma rising to the surface and causing tremors,” said Sutopo Purwo Nugroho of the National Disaster Management Agency.

“There should be zero public activity within the specified radius in case there is an eruption.”

However, flights at Bali’s international airport are operating as usual and there is little disruption to tourism operators across the rest of the Indonesian island.

Nearly 6000 people had been moved so far and that number was expected to rise, officials said.

Indonesia straddles the “Pacific Ring of Fire”, where several tectonic plates meet and cause 90 per cent of the world’s seismic activity.

The country has nearly 130 active volcanoes, more than any other country.