Agencies, Jakarta – Jakarta's main airport and three others extended their closure to 6 p.m. on Monday after being forced to halt operations due to a volcanic eruption, leaving tens of thousands of passengers stranded.
Eight airports halted operations over the weekend after ash was detected in their airspace, disrupting hundreds of flights and leaving more than 170,000 passengers stranded, according to the transport ministry.
At least four airports, including Jakarta's Soekarno-Hatta International Airport, extended their closure from Monday morning to 6 p.m. (1100 GMT), airport operator Angkasa Pura said in a social media post.
"In connection with the increasing eruption activity of Mount Anak Krakatau, flight operations at several airports have been suspended; passengers are advised to regularly monitor their flight status with the respective airlines," the operator said.
Halim Perdanakusuma, a smaller airport that caters to both civil and military flights, also extended its closure, the company said.
The probability of an eruption remains high until Monday morning, the country's geology agency said.
"The threat from an eruption comes from the ejection of incandescent rocks accompanied by heavy ashfall. Another potential hazard arises from lava flows if the eruption resumes and continues," the agency said.
The volcano monitoring agency's website showed the most recent Anak Krakatau eruption occurred Sunday at 8:23 p.m.
The agency warned on Monday that "the probability of further eruptions in the coming periods remains high."
The eruptions have seen ash reach as high as 6,000 meters on the Java side of the volcano and 15,000 meters on the Sumatra side and some parts of Banten province in Java, the Meteorology, Volcanology and Geophysics Agency (BMKG) posted on its website.
On Sunday, the disaster agency called for people to wear masks while travelling outdoors to avoid breathing in the ash. In Jakarta and Lampung, schools will use remote learning to counter health risks for students, state news agency Antara reported.
Anak Krakatau sits in a strait that separates the islands of Java and Sumatra.
The volcano has been sporadically active since it emerged from the sea at the beginning of last century in the caldera that formed after the 1883 eruption of Mount Krakatau.
A 2018 tsunami triggered by a collapse of parts of Anak Krakatau killed 429 people and left thousands displaced.