Efforts in Indonesia began to evacuate about 12,000 residents from their homes on Wednesday following the eruption of the Ruang volcano.
The volcano erupted on Tuesday, spewing lava and rocks, with the authorities raising the alert level to the highest possible and warning of potential pyroclastic flows, deadly ash surges and the possibility of a tsunami.
Mount Ruang, which is situated in the Sangihe Islands arc of the North Sulawesi province, has been increasingly active in recent weeks.
The eruption also led to a power outage on neighboring Tagulandang island.
Sam Ratulangi International Airport in Manado was forced to shut down, disrupting air travel in the region, officials said.
Authorities have extended the airport's closure until noon (0800 GMT) on Thursday.
"Personnel of Manado Search and Rescue Agency are evacuating 109 Tagulandang residents to Munte port, while hundreds are still waiting in Minanga port to be evacuated," the National Search and Rescue agency said in its statement on Wednesday.
Abdul Muhari, the spokesman for the National Disaster Management Agency, said 12,000 residents who live within a 7-kilometer (4.4-mile) radius of the volcano would have to be evacuated.
He added that residents were being evacuated by ferries operated by the National Search and Rescue Agency, the Indonesian navy and police.
"We will ensure that they are prohibited from leaving the evacuation shelters to return home during the extended emergency response period of up to 14 days, or until conditions are completely normal," he said in a statement.
Indonesia sits on the "Pacific Ring of Fire," an area of high seismic activity where multiple tectonic plates meet.
