Indonesia raises Anak Krakatau alert to Level III after 13 eruptions recorded in a day

Nevin Al Sukari - Sana'a - Mount Anak Krakatau billows smoke from its crater, and lava flows (invisible during the daytime) send up clouds of steam as they hit the sea, as seen from the waters of the Sunda Strait on September 12, 2026. Indonesia’s Anak Krakatau volcano has shown renewed activity, recording at least 13 eruptions yesterday and prompting authorities to raise its alert status to Level III. — AFP pic

First Published: Saturday, 10 Oct 2026 10:38 AM MYT

Last Modified: Saturday, 10 Oct 2026 10:39 AM MYT

JAKARTA, Oct 10 — Indonesia’s Anak Krakatau volcano has shown renewed activity, recording at least 13 eruptions yesterday and prompting authorities to raise its alert status to Level III, the second-highest level in the country’s four-tier volcanic alert system.

The Geological Agency said the alert was raised from Level II effective 9pm local time yesterday, following an assessment of volcanic activity since early this month.

“Signs of increased activity on a low scale began to emerge in early October 2026,” the agency said in its assessment dated October 9.

It noted however, that seismic monitoring had not indicated a significant overall increase in volcanic earthquakes.

Anak Krakatau, located in the Sunda Strait between Java and Sumatra, was downgraded to Level II on September 21 following a reduction in volcanic activity, after remaining at Level III since early September.

The latest activity follows a series of major eruptions in early September that sent volcanic ash into the atmosphere, forcing temporary airport closures. The event disrupted 2,961 flights and affected about 341,000 passengers.

According to eruption reports published on the Volcanology and Geological Hazard Mitigation Centre’s (PVMBG) website, yesterday’s documented eruptions included one at 4.17pm that sent an ash column 250 metres above the summit, followed by another at 4.30pm with a 150-metre column.

Eleven further eruptions were recorded between 6.28pm and 9.20pm, although their ash columns could not be observed. PVMBG’s full-day seismic monitoring recorded 26 eruption earthquakes.

Apart from yesterday’s 13 individually reported eruptions, Anak Krakatau recorded at least five others earlier this month — four on October 5 and one on October 8 — bringing the documented minimum to 18 since the beginning of October.

The Geological Agency said satellite monitoring detected sulphur dioxide emissions ranging from 71 to 237.5 tonnes per day between September 21 and October 9, while incandescence had been observed at the volcano since October 6.

Meanwhile, according to an advisory issued by Australia’s Darwin Volcanic Ash Advisory Centre (VAAC), volcanic ash reached an altitude of about 1.8 kilometres above sea level at 10.50pm yesterday, drifting westward over the Sunda Strait towards the Indian Ocean at approximately nine kilometres per hour, before being forecast to dissipate within six to 12 hours.

The Geological Agency warned residents, visitors, and tourists of volcanic rocks, heavy ashfall, lava flows, and secondary eruptions, and prohibited all from entering a five-kilometre radius of the eruption centre and areas within one kilometre of two newly formed islands northwest and southeast of Anak Krakatau.

It also urged coastal communities in Banten and Lampung provinces to remain calm, avoid spreading unverified tsunami claims, and follow official safety instructions. — Bernama