Thousands flee as Sumatran volcano erupts after 400 years

A volcano erupted spectacularly on the Indonesian island of Sumatra early yesterday morning, sending plumes of ash, sand and steam 1500 metres into the sky and prompting the evacuation of 12,000 nearby residents.

Mount Sinabung has not erupted for more than 400 years and authorities admitted yesterday they had not been monitoring it closely and knew little about its potential for further explosions.

The 2460-metre volcano in the north of Sumatra began fizzing and spitting smoke for several hours on Friday, emitting loud noises and panicking residents.

Grey ash continued to gush from the volcano on Saturday but authorities remained confident that it would not erupt. Those calculations proved misplaced when it did just that after midnight on Sunday.

While there were no serious lava flows, hot sand and ash blanketed vegetation and farms up to 30 kilometres away, setting trees alight near the mountain's top.

A six-kilometre exclusion zone has been set up around the volcano. Residents of 14 villages were moved from the area and into government buildings, mosques and other buildings as they prepare for further large discharges.

There were no casualties from the eruption, although a woman died of an existing illness during the evacuation. Some villagers had stayed behind to prevent looting, Indonesian media reports said.

''The last time the volcano erupted was back in 1600,'' Priyadi Kardono, spokesman for the Indonesian National Disaster Management Agency, said.

''Therefore we have limited data on what kind of eruption we can expect from it. We have a team now there to research and compile data of what type of volcanic eruption we might expect, should it erupt again.''

Mr Priyadi said the volcanic activity appeared to be decreasing but the highest level of warning would remain in place for the next week due to the uncertainty.

Indonesia is situated on the ''ring of fire'', one of the world's more tectonically active areas.

The eruptions of Mount Tambora in Sumbawa and Mount Krakatoa in the Sunda Strait are among the biggest volcanic blasts in recent history, both leading to a temporary cooling of the Earth's temperature as debris from their explosions travelled around the atmosphere.

About 70,000 years ago on Sumatra, a supervolcano at Toba erupted, creating a ''mega-colossal'' event that is thought to have produced a decade-long global winter and to have reduced the world's population to just 10,000.

Its crater is now a 100-kilometre-long lake and is a popular tourist destination.