REPUBLIKA.CO.ID, MEDAN -- The number of local residents killed in an eruption of Mount Sinabung located in Karo District, North Sumatra, climbed to six, and three others were in critical condition.

"Provisional data show that there were nine victims, comprising six deaths and three sustaining serious burn injuries due to hot clouds of ash," spokesman of the National Disaster Mitigation Agency (BPBN) Sutopo Purwo Nugroho told the press here, Sunday.

The victims are residents of Gamber Village, Simpang Empat Sub-district, Karo District, North Sumatra.

The volcano erupted and unleashed hot clouds of ash on May 21 at 4:48 p.m. local time.