Jakarta [Indonesia], April 18 : More than 11,000 people have been evacuated after a volcanic eruption in the province of North Sulawesi Indonesia, Al Jazeera reported on Thursday.
According to Al Jazeera, Mount Ruang, first erupted at 9: 45 pm local time on Tuesday and then four times on Wednesday.
The volcanology agency in Indonesia increased the mountain's alert level to four, the highest on the scale, which is 725 metres (2,379 feet) high.
The agency also expanded the size of the exclusion zone surrounding the crater from four to six kilometres (2.5 to 3.7 miles). Initially, more than 800 residents of Ruang were evacuated to Tagulandang Island, which is close by and situated more than 100 kilometres (62 miles) north of Manado, the provincial capital, according to Al Jazeera.
Officials said on Thursday morning that more people will have to be evacuated and brought to Manado due to the expanding exclusion zone.
"At least 11,615 residents who are in the risk area must evacuate to a safe place," Abdul Muhari, the head of the disaster agency's disaster data, communications and information centre, was quoted as saying by the Kompas newspaper, according to Al Jazeera.
Authorities are also concerned that, as happened during an earlier eruption in 1871, a portion of the volcano may collapse into the sea and trigger a tsunami.
Sam Ratulangi International Airport in Manado will remain closed until at least Thursday evening, according to aviation authorities, "due to the spread of volcanic ash, which could endanger flight safety," reported Al Jazeera.
The airport offers flights to South Korea, China, and Singapore, among other nations.
Flights to and from Kota Kinabalu International Airport in adjacent Malaysia had severe disruptions as well. Situated on the northernmost point of Malaysian Borneo, Kota Kinabalu is roughly 1,100 kilometres (688 miles) northwest of Ruang.
Following two earthquakes in recent weeks, Mount Ruang's activity has seen a surge, according to the country's volcanology service.