Mayon volcano stirs back to life

Mayon has erupted 47 times in the past

LEGAZPI, Philippines -- Mayon volcano in the Philippines has blasted back to life, spewing out fiery rocks in an explosion that suggests more eruptions could be on the way.

Scientists said Monday that an estimated 50,000 villagers wishing to return to their homes around the mountain's base would have to reconsider.

The 2,460-metre (8,000-foot) volcano reminded observers of its awesome power in an explosion that left the local population pondering their immediate future.

"Clear visual conditions last night (Sunday) revealed forceful expulsion of incandescent lava fragments ... accompanied by jet-like roaring sounds," the Philippine volcanology institute said in a statement.

Mayon, one of 22 active volcanoes in the Philippines has erupted 47 times previously. In its deadliest blast in 1814, the volcano killed 1,200 people as it buried a town under mud and rocks, leaving only the church steeple visible.

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Scientists said the number of tremors picked up from the volcano since the latest series started on July 26 continued to increase and that Mayon's emissions of sulfuric fumes remained at the high rate of 4,800 tonnes a day -- far above normal levels of 500 tonnes.

"(This) means it is in state of hazardous eruption with significant potential to erupt more explosively," the institute said.

Relief officials said they had allowed some evacuees to return to their homes because they lived in villages outside the designated danger zone more than seven km (four miles) from the volcano's summit.

"We have increased our watch on areas within the danger zone to prevent the others from also going back," chief provincial relief officer Cedric Daep said.

No casualties have been reported since the current series of eruptions began.

Experts said Friday high sulfur-dioxide emissions and quakes indicated Mayon could explode again and send clouds of ash and rock fragments down the slopes.

Known as pyroclastic flows, the clouds can reach speeds of up to 60 miles an hour and temperatures of 1,300 degrees, incinerating anything in their path.

While volcanic activity has lessened since Thursday's eruption, areas around Mount Mayon were shrouded in grey ash on Friday and volcanic mud was beginning to harden.

Residents complained of eye irritations from the sulfur and dust-laced atmosphere.

Reuters contributed to this report.