Rescue efforts resume with East Java on high alert as Indonesia's Mount Semeru erupts

Search and evacuation efforts resumed on Monday as improved weather allowed rescuers look for possible victims, after a volcano on Indonesia’s most densely populated island erupted the previous day.

Thousands of residents in Indonesia's East Java were on high alert as authorities imposed an 8km no-go zone and forced the evacuation of entire villages.

The provincial search and rescue agency deployed teams to the worst-affected areas near Mount Semeru to assess damage, with low rainfall giving some reprieve, National Search and Rescue Agency spokesman Tholib Vatelehan said.

“Yesterday, the rainfall level was high, causing all the material from the top of the mountain to come down. But today, so far, there's no rain, so it's relatively safe,” he said.

No casualties have been reported and there has not been any immediate disruption to air travel.

The 3,676-metre volcano erupted at 2.46pm local time on Sunday.

Footage shot by local residents showed Mt Semeru spewing a giant cloud of grey ash high above its crater, which later engulfed the mountain and surrounding rice paddy fields, roads and bridges and turned the sky black.

A video shared by the Environment Ministry on Twitter showed a fast-moving stream of lava, rocks and hot gases — known as a pyroclastic flow — gushing down the mountainside.