Indonesian volcano critical, may erupt: scientist
SUGIHWARAS, Indonesia (Reuters) - Indonesia's Mount Kelud volcano in East Java is in a critical phase and could erupt any time after being shaken by more than 1,000 tremors over the last two days, the country's top volcano expert said on Friday.
An estimated 350,000 people live within 10 km (6 miles) of the volcano and when it last erupted in 1990 at least 30 people were killed.
Authorities raised the alert at Mount Kelud to maximum two weeks ago amid signs of an imminent eruption, although its crater lake makes it harder to monitor than many volcanoes.
"Kelud is in a critical phase. It could erupt now," Surono, head of Indonesia's centre for Vulcanology and Geological Hazard Mitigation, told Reuters by telephone from the capital Jakarta.
Another official near the site said there had been more than 600 tremors on Thursday and hundreds more overnight.
"Tremors stopped for a moment but they have started again. From midnight until 6 a.m. we recorded 559 tremors," said Umar Rosadi, a vulcanologist at a monitoring post near Kelud.
"We continue to monitor the activity, but we can't tell when an eruption will happen."
He said magma was 700 meters (2,296 feet) below the crater.
In 1919, about 5,000 died as Kelud ejected scalding water from its crater lake.
After the alert was first raised recently, more than 100,000 people were ordered to evacuate from around the volcano, 675 km (420 miles) east of the capital Jakarta but only 90 km (55 miles) southwest of Indonesia's second-largest city of Surabaya.
Thousands have left from a 10-km (6-mile) zone around Kelud, but many had returned home, fearing for the safety of their possessions.
Police in Sugihwaras, a village 8 km (5 miles) from the crater that suffered casualties and was badly damaged during an eruption in 1990, used megaphones to urge remaining villagers to leave.
"I returned home two days ago and just finished cleaning the house. Now I have to go back to the shelter again because they say the situation is dangerous," said Sukartun, a 35-year-old housewife.
In recent weeks, there have been periods of intense seismic activity at the volcano followed by calm, although the high temperature of the crater lake and other observations have led experts to keep the alert status at maximum.
On October 19, there was a surge in tremors at Kelud, but the activity later subsided and there was no eruption.
Some scientists have suggested that hardened larva from previous eruptions could be blocking the release of magma, but warn that it could burst out when the energy has built up enough.
Indonesia has faced a series of deadly natural disasters in recent years and has the highest number of active volcanoes of any country. It sits on a belt of intense volcanic and seismic activity know as the "Pacific Ring of Fire".
Indonesian officials were also closely monitoring three other volcanoes for increased activity.
(Additional reporting by Ahmad Pathoni and Telly Nathalia in Jakarta)
