Lumajang, East Java, July 17 -- Mount Semeru, located on the border of Lumajang and Malang districts in East Java, erupted twice on Thursday morning, with ash columns reaching as high as one thousand meters above the summit.

The first eruption occurred at 4:30 a.m. local time, producing an ash column approximately 800 meters above the summit. The ash column was observed to be gray, with moderate to thick intensity, moving westward.

The eruption was recorded on a seismograph with a maximum amplitude of 22 mm and a duration of 170 seconds.

"At 7:42 a.m. local time, Mount Semeru erupted again, with an ash column observed at approximately one thousand meters above the summit, or 4,676 meters above sea level," an officer at the Mount Semeru...