Volcanic ash from Mount Anak Krakatau disrupts flights and travel across Indonesia

About 170,000 passengers were left stranded on Sunday as Indonesia closed its main international airport and seven others, cancelling hundreds of flights after Mount Anak Krakatau spewed a plume of volcanic ash and lava from more than 150km away.

Schools across Jakarta were also affected with classes moving online on Monday, the city said in a statement, without specifying how long the measure would be in place.

Some shipping has also been disrupted.

The suspension has been extended until 8:59am Monday local time “due to increased eruptive activity at Mount Anak Krakatau”, the airport authority said in an Instagram post.

Anak Krakatau erupted on Saturday, producing a fountain of lava and booming sounds that could be heard up to a few hundred kilometres away, the geology agency said in a statement.

Two new eruptions were recorded on Sunday, said the country’s volcanology agency.

Ash from the volcano was detected in the airspace surrounding Soekarno-Hatta international airport, prompting authorities to suspend operations, the ministry said.

Operations have also been suspended at seven other airports including the Husein Sastranegara airport in Bandung and Radin Inten II airport near Bandar Lampung on Sumatra, the ministry said.

“To date, 1,558 flights have been delayed at the eight affected airports, with 170,000 passengers stranded,” the ministry said in a statement on Sunday.

More than 900 affected flights were to and from the Soekarno-Hatta, it added.

Several airports in cities including Semarang and Surabaya have been prepared as alternatives for landing, transportation minister Dudy Purwagandhi said.

The disruption left some passengers scrambling to find alternative flights.

Henny Yensan, 44, who had hoped to go back to her home town with her mother, said “everybody was disappointed”.

“No one flew into a rage because, after all, this is due to natural disaster,” the businesswoman who had to reschedule her flight to Tuesday told AFP.

Volcanic ash also reached the city of Bandar Lampung in the southern tip of Sumatra, blanketing parked cars and roadsides.

Anak Krakatau, which means Child of Krakatau, sits in a strait that separates the islands of Java and Sumatra.

Ships passing through the strait were asked to increase vigilance for possible disruption to navigation safety due to volcanic activities.

Vessels are prohibited from approaching an exclusion zone of a 3km radius from the volcano, local port authorities said in a statement.

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.

That disaster was one of the deadliest and most destructive in history with an estimated 35,000 people killed.

Geology agency head Lana Saria warned against approaching Anak Krakatau, saying materials ejected from the volcano could endanger those within the exclusion zone.

She said the most recent series of eruptions do not have the potential to trigger a tsunami.

A 2018 tsunami triggered by a collapse of parts of Anak Krakatau killed 429 people and left thousands displaced.

Indonesia, a South-east Asian archipelago nation, sits on the Pacific Ring of Fire, where the meeting of continental plates causes high volcanic and seismic activity.