Updated

More than 6,200 people were evacuated from their villages following the eruption of Mount Sinabung in western Indonesia, an official said Monday.   The 8,530-foot volcano in North Sumatra province erupted early Sunday after being dormant for three years, sending thick ash into the sky with small rocks pelting neighboring villages.

National Disaster Mitigation Agency spokesman Sutopo Purwo Nugroho said a total of 6.259 people have been evacuated as of Monday afternoon, and were being sheltered in eight locations. No damage was reported.

The official Antara news agency reported that five people were hospitalized in Kabanjahe, the capital of Karo District. It quoted Jhonson Tarigan, a spokesman of the local disaster mitigation agency, as saying the five were having difficulty breathing after inhaling volcanic ash.

Most of the displaced were from six villages within several miles of the mountain in Karo district, Nugroho said.

Local authorities prepared 2,000 blankets and distributed masks to displaced people. They also have set up a health command post, Nugroho said. He added there was an urgent need for cooking ware, food for babies and medicine.

On Monday, gray smoke still billowed from the peak of North Sumatra's tallest volcano, carrying ash eastward. Authorities asked residents to remain alert for other potential eruptions.

Mount Sinabung's last eruption in August 2010 killed two people and forced 30,000 others to flee. It caught many scientists off guard because they had failed to monitor the volcano, which had remained quiet for four centuries.

There are more than 129 active volcanoes in Indonesia, the world's largest archipelago nation. It is prone to seismic upheaval due to its location on the so-called "Ring of Fire" -- a series of fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.