Mount Merapi spat out near continuous clouds of deadly hot ash, rock fragments and volcanic gas early Monday, as activity at the volcano intensified to its highest level yet, an official and eyewitnesses said.
One of the eruptions sent a dark cloud of debris and ash almost four kilometers (2.5 miles) down the mountain's western flank, said Ratdomopurbo, the region's chief vulcanologist. It was followed by several other huge explosions on the crater.
Villagers who had not evacuated their homes gathered on the side of the road on the slopes of the volcano, which rises from the plains of Indonesia's densely populated Java Island. They were told to stand by for possible evacuation.
Scientists raised the alert status for Merapi on Saturday to the highest level after weeks of volcanic activity, and by Sunday more than 4,500 people living in villages closest to the crater or next to rivers that could provide paths for hot lava had been evacuated.
Some 18,000 others who live lower down the slopes of the 3,000-meter (9,800-foot) mountain and were not considered to be in immediate danger stayed behind.
Merapi, which is one of 129 active volcanoes in Indonesia, sent out a searing cloud of gas that burned 60 people to death when it last erupted in 1994. About 1,300 people died in a 1930 eruption.
The deadly clouds of ash, gas and debris are a big worry, said Sugiono, one of the scientists on a team monitoring the volcano 24 hours a day.
He said a glowing dome of lava being formed by magma forced to the surface was poised to collapse and could send searing clouds down the mountain at several hundred kilometers (miles) an hour, reports the AP.
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