Mount Sinabung in North Sumatra erupted Saturday morning, disaster mitigation agency spokesman Sutopo Purwo Nugroho told CNN. The victims were hit by hot ash clouds and were all found in Sukameriah, a village close to the volcano’s crater, he said.
At least three other people were injured.
The volcano spewed ash columns 2,000 meters (1.24 miles) high, Nugroho said.
Local search and rescue teams were scheduled to go on a recovery operation Sunday morning, he said.
Sinabung had been quiet for around 400 years until it erupted in 2010. It has been spewing gas since September.
Last month, intensifying volcanic activity displaced 22,000 people who live nearby.
The evacuees had been moved to temporary camps, and more than half were allowed to return home on Friday.
Saturday’s victims lived within a 3-kilometer radius of the volcano. Some were there checking on their homes or were there just to watch the eruptions, Nugroho said.
The government issued the highest level of alert for the latest eruptions.