Indonesia has raised the alert level for its most active volcano and authorities have ordered villages living on its slopes to evacuate.
Mount Merapi, on the densely populated island of Java, has erupted four times since Monday, sending out a 3,500m (11,483ft) column of ash and smoke.
The authorities are taking no chances after a series of eruptions in 2010 killed more than 350 people.
Indonesia’s geological agency raised the alert level for Merapi from normal to “beware” due to its increased activity.
Around 660 people living within a 3km (2 miles) exclusion zone
have evacuated since Tuesday, Sutopo Purwo Nugroho, a national disaster mitigation agency spokesman said.
Mr Nugroho told the Associated Press climbing and hiking on Merapi is banned and only disaster agency personnel or related researchers should enter the restricted area.
There have been no reports of casualties.
This month, the airport in Yogyakarta, the closest city to Merapi, was briefly shut down because of the eruptions.
Through the ages, Indonesians have tilled the fertile volcanic soil on the mountain’s slopes and more recently the volcano has become a tourist site.