Thousands of residents in Indonesia’s East Java were on high alert on Monday after a violent eruption at the island's tallest volcano prompted authorities to impose an 8-kilometre no-go zone and forced evacuations of entire villages.

The provincial search and rescue agency deployed teams to the worst-affected areas near Mount Semeru to assess the damage, with low rainfall giving some reprieve, Tholib Vatelehan, a Basarnas spokesperson, told Reuters.

People fled the eruption on motorcycles, with almost 2,500 people forced to evacuate, authorities said.

Indonesia’s volcanology and geological hazard mitigation agency on Sunday raised the alert level for Mt. Semeru to the highest level. The agency also issued a warning to residents not to approach within 8 km (5 miles) of the summit, or 500 metres of riversides due to risks of lava flows.

Semeru erupted last year killing more than 50 people and displacing thousands more.

The eruption, some 640 km (400 miles) east of the capital, Jakarta, follows a series of earthquakes in the west of Java, including one last month that killed more than 300 people.

An archipelago of 270 million that sits along the Pacific Ring of Fire, Indonesia is one of the most disaster-prone nations on earth.

With 142 volcanoes, Indonesia has the largest population globally living in close range to a volcano, including 8.6 million within 10km (6.2 miles).