Volcanology and Geological Disaster Mitigation Center raised the status of Mount Sangeang Api on Sangeang Island, Bima regency, West Nusa Tenggara (NTB), to alert after volcanic activity continued to increase over the past two weeks.
Local residents and visitors have been warned to stay outside a 5-kilometer radius from the crater. The mountain has been closed to climbers.
The head of Mt. Sangeang Api observatory post, Hadi Pramono, said the warning status of the volcano, which is 1,981 meters above sea level, was raised to cautious in December. "As volcanic activity has continued to increase since May 11, Mt. Sangeang Api's warning level has been raised to alert," he told The Jakarta Post on Wednesday.
Hadi said the increased volcanic activity could be seen from the increasing intensity of volcanic and tectonic tremors and 15-meter high white smoke coming from the crater.
He said the center had informed Bima administration and the regency's Disaster Management Agency of the increased warning status of Mt. Sangeang Api and urged them to maintain vigilance.
Mt. Sangeang Api is located on the 152-square-kilometer Sangiang Island and the closest village is Sangeang, Wera district, Bima regency, NTB.
Hadi said there was no settlement on Sangeang Island, but residents of Sangeang village and its surrounding areas often visited the island to work the soil. According to data from the NTB provincial energy and mineral resources agency, the last eruptions were in 1997 and 1999, while the largest in 1985 forced local farmers to flee to Sangeang Darat village.