for National Geographic News
Indonesian officials began evacuating 11,000 people from around the Merapi volcano today, as lava and clouds of gas and debris poured down its steep, upper slopes, news agencies reported.
The 9,700-foot (2,900-meter) volcano on the Indonesian island of Java has been sporadically spewing clouds of toxic gas and lava for several weeks.
Experts believe a major eruption could come at any time.
Villagers were being trucked away from the foot of the mountain to temporary shelters.
"Of course it is dangerous. But we don't know for sure whether the lava dome will collapse," Subandriyo, a government volcanologist who uses only one name, told the Associated Press.
Officials said a cloud of gas from Merapi stretched for 2.4 miles (4 kilometers), and piles of lava were pushed up to 4 miles (7 kilometers) from the crater, according to the news reports.
Activity in the region has increased since a magnitude 6.3 earthquake struck about 20 miles (30 kilometers) to the south of the volcano on May 27.
The earthquake killed more than 5,800 people.
Scientists believe the earthquake may have contributed to the increased activity at the volcano.
"I don't think that's unreasonable. The volcano is an unstable pile of rock. It's fragile," said Stanley Williams, a volcanologist at Arizona State University in Tempe who has studied Merapi.
"I would be surprised if [the earthquake] didn't literally shake the mountain," he added.
A major eruption of Merapi could strain quake-relief efforts.