Mayon volcano in the Philippines erupted with little warning today, hurling flaming ash 10 kilometres (six miles) into the air and forcing about 25,000 villagers to flee their homes.
No casualties were reported, but residents of the provincial capital Legazpi, 11 kilometres from Mayon's crater, rushed out of their homes in panic as ash showers - known as black rain - fell on the city of 130,000 people, governor Mr Alfrancis Bichara said.
People have sought refuge in school houses and other government buildings around Legazpi, he said.
Located in Albay province 330 kilometres southeast of Manila, the volcano produced eruptions on June 24th but subsided 10 days later.
It re-erupted at 7.56 a.m. (23.56 p.m. Irish time Wednesday) when columns of burning ash shot out of its mouth, darkening Legazpi city and surrounding towns.
The avalanche rolled as far as 5.5 kilometres from the summit, the Philippine Institute of Vulcanology and Seismology said.
The institute had maintained an alert level of three since the last eruptions subsided, meaning there was unrest in the volcano but chances of an eruption were days or weeks away. It raised the alert level only four hours before the eruption.
Mayon, one of the Philippines' 22 active volcanos, has a history of 47 violent eruptions. Its deadliest blast occurred in 1814 when it buried a town under mud and rocks and killed 1,200 people.