Indonesian authorities raised the alert level for Mount Bur Ni Telong in Aceh, the westernmost province of Indonesia, to its second highest level, an official said. The move came after increased volcanic activity and a rise in earthquakes, including events that were felt in nearby areas.
The alert affects the 2,624-meter (8,600-foot) stratovolcano in Aceh’s Bener Meriah regency. Lana Saria, the acting head of the Geological Agency at the Energy and Mineral Resources Ministry, said the volcano recorded at least seven earthquakes on Tuesday evening, and that the tremors were felt about 5 kilometers (3 miles) away.
Saria said seismographs also detected seven shallow volcanic earthquakes, along with 14 deep quakes and two tectonic quakes. She said the alert level was raised from the third to the second highest level Tuesday evening after results from visual and instrumental monitoring showed increased volcanic activity.
“Aftershocks following local tectonic events indicate magma activity is easily triggered by tectonic disturbances,” Saria said. She added that the increase in seismic activity has been ongoing since July and became more intense and shallow in the past two months.
The agency’s visual monitoring showed the volcano clearly visible with no crater smoke. Even so, Saria warned of possible eruption, including phreatic blasts and hazardous volcanic gases near areas with fumaroles and solfataras, openings in the Earth’s crust that emit steam and gases.
Authorities urged residents and visitors to stay at least 4 kilometers (2.4 miles) from the crater. They also urged people to avoid fumarole and solfatara zones during cloudy or rainy weather because gas concentrations can be life-threatening.
The heightened alert came as Bener Meriah was still recovering from catastrophic floods and landslides earlier this month, which struck 52 cities and regencies on Sumatra island. The National Disaster Management Agency said the disasters killed 1,154 people, left 165 residents missing, and injured more than 7,000 others.
In Bener Meriah alone, the floods and landslides killed 31 people and left 14 missing, disrupting access to remote villages and displacing more than 2,100 residents. Tagore Abubakar, the regent of Bener Meriah, said more than 2,500 residents in the four villages most at risk were evacuated to government shelters.
Abubakar said authorities feared that heavy rains combined with volcanic activity could worsen conditions and complicate evacuation efforts. He said some residents had also fled to their relatives’ homes in neighboring Central Aceh regency.
Indonesia, an archipelago of more than 280 million people, has over 120 active volcanoes and is prone to volcanic activity because it sits along the “Ring of Fire,” a horseshoe-shaped series of seismic fault lines around the Pacific Ocean.