Mount Anak Krakatau alert raised to Level III after activity surge

Jakarta (ANTARA) - Indonesia’s Geological Agency on Friday raised the alert status level for the Anak Krakatau volcano to Level III, the second-highest tier on its four-level warning system, following a significant surge in volcanic activity.

Authorities have established a five-kilometer (3.1 miles) exclusion zone around the active crater, warning residents, fishermen, and tourists to clear the area due to the threat of a potential eruption and flying incandescent material.

Anak Krakatau, located in the Sunda Strait between the western coast of Sumatra's Lampung province and Java's Banten province, historically triggered a devastating tsunami in 2018 after a massive collapse of its crater wall, which killed over 400 people.

Lana Saria, the Acting Head of the Geological Agency of the Ministry of Energy and Mineral Resources, stated in Jakarta that the decision to escalate the alert status from Level II to Level III was driven by recent visual and instrumental monitoring data.

"The increase in activity indicates a magma supply moving toward the surface," Saria said. "Therefore, the public and tourists are requested not to approach the active crater within the recommended radius."

Monitoring data recorded a sharp rise in volcanic earthquakes, changes in the volcano's deformation, and surface activity indicating magma accumulation in the shallower parts of the chamber.

Furthermore, tiltmeter data from several observation stations showed an inflation trend, signaling increasing pressure inside the volcanic body.

Residents along the coastal areas of the Sunda Strait have been urged to remain calm but vigilant, and to strictly follow directions from local governments and volcano monitoring officials.

Local administrations and relevant agencies have been instructed to prepare mitigation plans and strengthen coordination in anticipation of further activity.

The Geological Agency noted that Anak Krakatau is under intensive 24-hour surveillance through seismic, deformation, and visual observation networks to ensure early detection of any escalations.

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Translator: M. Riezko Bima Elko Prasetyo, Aditya Eko Sigit Wic

Editor: Bayu Prasetyo

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