RRI.CO.ID, Lumajang - Mount Semeru, located on the border of Lumajang and Malang regencies, East Java, recorded two successive eruptions on Saturday morning, May 2, 2026. Both eruptions sent ash columns approximately 700 meters above the peak.

The first eruption occurred at 06.56 local time, with a thick white-to-gray ash column observed leaning toward the southwest and west. The event was recorded on a seismograph with a maximum amplitude of 22 mm and lasted 105 seconds. Just minutes later, at 07.05 local time, a second eruption followed with identical plume heights and similar seismic characteristics, lasting 103 seconds.

"The first eruption occurred at 06.56 local time with an observed eruption column height of about 700 meters above the peak or 4,376 meters above sea level," reported an officer at the Mount Semeru Observation Post, Sigit Rian Alfian,as quoted by Antara.

Mount Semeru currently remains at Level III (Alert), prompting authorities to issue strict safety recommendations for both residents and visitors due to ongoing volcanic activity. Within the restricted zones, all activities are strictly prohibited in the southeastern sector along Besuk Kobokan up to 13 kilometers from the summit.

Regarding river safety, people are advised to maintain a distance of at least 500 meters from the riverbanks of Besuk Kobokan beyond the initial restricted zone, as pyroclastic flows and lahars could potentially travel up to 17 kilometers. Additionally, a mandatory summit radius restriction is in place, prohibiting any activity within five kilometers of the crater to protect against the danger of ejected incandescent stones.

Officials are urging the public to remain vigilant regarding potential hot clouds, lava flows, and lahars along the valleys and rivers originating at the summit. This includes Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as smaller tributaries. The high-intensity ash observed in today's eruptions underscores the mountain's volatile state. ***