More than 5,000 people have fled their homes in western Indonesia in recent days following a series of violent volcanic eruptions, an official said Tuesday.

Mount Sinabung on the north of Sumatra island has been hurling out red-hot ash, rocks and torrents of glowing lava up to seven kilometres (four miles) into the air since the start of the month.

Villagers from nearby Karo district are being evacuated as the volcano, which erupted in September for the first time since 2010, continues to spew ash and rocks.

"So far, 5,265 people have been evacuated from seven villages," local government spokesman Robert Peranginangin told AFP.

"They were all very scared as the volcano has not shown signs of slowing down."

Although the government has called for people living within three kilometres (1.9 miles) of the volcano to be evacuated, Peranginangin said those living beyond the danger zone were also fleeing their homes.

"They just don't feel safe and are panicking. They prefer to stay in shelters, like mosques and churches," he said, adding the number of evacuees was expected to go up.

National disaster agency spokesman Sutopo Purwo Nugroho said the volcano erupted again early Tuesday, spewing clouds of hot gas, although the eruption was smaller than on previous days.

Indonesia has dozens of active volcanoes and straddles major tectonic fault lines known as the "Ring of Fire" between the Pacific and Indian oceans.

In August five people were killed and hundreds evacuated when a volcano on a tiny island in East Nusa Tenggara province erupted.

The country's most active volcano, Mount Merapi in central Java, killed more than 350 people in a series of violent eruptions in 2010.