Ships Warned to Clear 3 km from Krakatau as Volcano Forces Airport Closures Across Java

Indonesia's transport ministry put an exclusion zone around Anak Krakatau on Saturday after the volcano sent ash columns rising to 50,000 feet over the Sunda Strait. All vessels are barred from within three kilometres of the crater and must watch for ejected material, volcanic ash, and navigation hazards while transiting the strait.

Ferry crossings between Java and Sumatra stayed open throughout the eruption. Operators raised alert levels and tracked ash drift to route clear of the worst plumes, with the government keeping the main Sunda Strait services running.

On land the picture was harder. Soekarno-Hatta and seven other airports suspended flights, cancelling 301 services and delaying more than 1,550 others. About 170,000 passengers were left stranded. Ash blanketed schools and fish markets from Jakarta to coastal Sumatra, forcing closures across both islands.

Anak Krakatau, the island that grew from the site of the 1883 eruption, has been one of Indonesia's most active volcanoes. Its current Level III (Alert) rating allows the strait to keep moving, but the ministry's advisory puts the responsibility on skippers to maintain distance and track the evolving ash plume.

Shipping through the Sunda Strait links the Java Sea to the Indian Ocean, making it one of Southeast Asia's busiest routes. Earlier this month Indonesia joined Malaysia and Singapore to reaffirm open and safe transit through the region's straits at the 17th Malacca Strait Co-operation Forum. Closer to home, an Indonesian cargo vessel caught fire off Sulawesi on 1 September, killing two crew, a reminder of how quickly routine passages through these waters turn dangerous.