Costa Rica volcano spews ash in biggest erruption for 100 years

© OVSICORI/AFP

Steam and ash spews from a vent inside the crater of the Turrialba volcano in Costa Rica.

The biggest eruption in a century at a volcano in Costa Rica has rained ash over the Central American country and prompted authorities to evacuate some communities.

Emergency services and scientists remained on high alert on Friday after the overnight explosion at the Turrialba volcano, close to the capital San Jose.

Volcanologist Gino Gonzalez said that the volcano had been rumbling and producing seismic activity since Wednesday evening.

He said the explosion caused the side of the crater to collapse, and ashfall was recorded in four provinces.

© PA

Smoke columns rising from the Turrialba Volcano after an eruption.

"We saw fiery explosions. We must confirm whether it was lava or burning material that fell so spectacularly," Raul Mora, a volcano expert with the National Seismological Network told local television, adding the volcano was highly active.

The last time Turrialba spewed lava was around 1863, Mora said.

The national park around the volcano has been closed since 2010, when it also spewed ash, as a precautionary measure, according to the emergency services.

A yellow alert was declared for communities near the volcano, which were evacuated. Agriculture Ministry officials were attending to some 400 head of cattle on Friday in areas where ash fell.