LUMAJANG, Jan 12 — Mount Semeru, located on the border of Lumajang and Malang Districts in East Java, erupted last night, sending pyroclastic flows as far as five km from the summit, reported ANTARA news agency.
"Mount Semeru erupted at 10.25pm local time. The eruption consisted of a pyroclastic flow with a distance of approximately 5km," said Mount Semeru Observation Post officer Sigit Rian Alfian in a written report.
The eruption column, locally known as hot clouds, was observed to be approximately 2,000 metres above the summit, or 5,676 metres above sea level.
This latest activity follows a period of heightened unrest for the volcano, which has remained frequently active for several years.
"The ash column was observed to be white to grey in colour, with thick intensity toward the east and southeast," he said.
Mount Semeru's eruption was recorded on seismographs with a maximum amplitude of 27 millimetres and a duration of 696 seconds.
It remains at Level III alert status. The authorities have advised the public to refrain from all activities in the southeastern sector along Besuk Kobokan, within 13km of the summit.
Beyond that distance, people are prohibited from engaging in activities within 500 metres of the Besuk Kobokan riverbanks due to the risk of pyroclastic and lava flows expanding up to 17km from the peak.
"The public is advised not to engage in activities within a five km radius of the crater/peak of Mount Semeru due to the risk of ejected incandescent rocks," Sigit said.
Residents are also warned of potential pyroclastic flows and lava flows moving through rivers and valleys that originate from the summit of Mount Semeru, particularly in Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, including smaller tributaries of Besuk Kobokan that may also be affected by the lava.
