Indonesia's Semeru volcano erupted on Wednesday and the country's volcanology agency increased the alert level of Java Island's tallest mountain to the highest.
The volcano spewed ash clouds as high as 2 km (1 mile) above the mountain's peak, the agency said, adding residents should keep to a 2.5 km distance away due to risks.
Semeru, more than 3,600 metres (12,000 feet) high, is one of Indonesia's nearly 130 active volcanoes.
Indonesia straddles the "Pacific Ring of Fire", a highly seismically active zone, where different plates on the earth’s crust meet and create a large number of earthquakes and volcanoes.

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