A huge volcano has sent an enormous 3,937ft column of ash into the air after erupting six times in one day.

Mount Semeru, in East Java, Indonesia, has been on a high level active alert for several years
Mount Semeru, in East Java, Indonesia, has been on a high level active alert for several years
Mount Semeru, in East Java, Indonesia, has been on a high level active alert for several years. The eruption has left torrents of mud flowing through towns, leaving a trail of destruction in its wake.

Massive mudslides have been seen flowing through the streets, taking huge chunks of debris along with them. The eruption happened at around 5.45am local time this morning, with plumes of 1,200 metres seen above the summit.

The volcano, which lies on the border between the Lumajang and Malang regions, is currently on a Level III alert status, according to the state-run Antara News. The outlet said the volcano erupted six times on Sunday morning.

"An eruption occurred on December 21, 2025, at 5.45am local time, with an observed column height of 1,200 metres above the summit," said Mount Semeru Observation Post Office, Liswanto, in Lumajang. People have now been warned by the Center for Volcanology and Geological Hazard Mitigation to stay 13km away from the volcano.

Beyond that, people have been warned that for a 17km radius, they should stay 500 metres from riverbanks due to the potential for pyroclastic and lava flows.

Pyroclastic flows are superheated, fast-moving avalanches of volcanic gas, ash and rock fragments that can reach hundreds of miles an hour and temperatures in excess of 1,000C.

"The public is also prohibited from activities within a 5 km radius of the crater due to the risk of ejected rocks," Liswanto said.

He warned residents to remain on high alert for hot ash clouds, lava flows and lahars along rivers and valleys originating from the volcano, which are fast-moving volcanic mudflows or debris flows of water mixed with volcanic ash, rock, and debris.