Authorities in western Indonesia are evacuating more villagers living near a volcano that's been rumbling for weeks.

Government volcanologist Gede Suantika says at least 28 hot ash avalanches occurred at Mount Sinabung on Monday and that there are indications the crater's lava dome continues to grow in size.

Subur Tambun, head of the local disaster mitigation agency, said hundreds of residents were being evacuated Monday from three villages.

Subur said 99 families were moved from a village on Saturday when the mountain unleashed a new powerful burst, sending hot ash as far as 3 kilometers (2 miles) down its southeastern slopes.

Authorities have been closely monitoring 2,460-meter-high (8,070-foot) Mount Sinabung on Sumatra island since June 2, when its threat status was raised to the highest alert level.