Chile's Puyehue volcano, dormant for decades, erupted on Saturday, belching an ash cloud more than 6 miles high.

The volcano, in south-central Chile, was spewing molten rocks on the Argentine city of Bariloche, but there was no visible lava flow, Xinhua news agency reported quoting officials.

Local authorities have declared “red alert” across the city and closed the local airport at tourist resort San Carlos de Bariloche. More than 3,500 people were evacuated from their homes near the volcano, Chile’s government said on Sunday.

Ash clouds fanned by easterly winds blew over the Andes, flooring several cities in neighboring Argentina. The volcano eruption also prompted Chilean authorities to close a heavily traveled border crossing into Argentina.

The volcano is nearly 1,000 kilometers south of Chile’s capital, Santiago. Chile has experienced a series of volcanic eruptions in recent years. It has a chain of about 2,000 volcanoes, the world's second largest after Indonesia.

Chilean Volcano Erupts
Lightning bolts strike around the Puyehue-Cordon Caulle volcanic chain near southern Osorno city in Chile. REUTERS/Ivan Alvarado
A plume of light-coloured ash stretches along the edge of the Andes, as the eruption at the Puyehue-Cordon Caulle volcano chain continues.
A plume of light-coloured ash stretches along the edge of the Andes, as the eruption at the Puyehue-Cordon Caulle volcano chain continues. Reuters
Overview of the ash-covered mountain resort of San Martin de Los Andes in Argentina039s Patagonia region
Overview of the ash-covered mountain resort of San Martin de Los Andes in Argentina's Patagonia region Reuters
View of the Lago Lacar and a part of its coast covered with ashes from Chile039s Puyehue-Cordon Caulle volcano chain in the mountain resort San Martin de Los Andes
View of the Lago Lacar and a part of its coast covered with ashes from Chile's Puyehue-Cordon Caulle volcano chain in the mountain resort San Martin de Los Andes Reuters
A resident walks through fallen ash from Chile039s Puyehue-Cordon Caulle volcano chain in the mountain resort San Martin de Los Andes.
A resident walks through fallen ash from Chile's Puyehue-Cordon Caulle volcano chain in the mountain resort San Martin de Los Andes. Reuters
A car travels along a road covered with ashes near the erupting Puyehue volcano near Argentina039s border.
A car travels along a road covered with ashes near the erupting Puyehue volcano near Argentina's border. Reuters
People gather on a road covered with pumice rocks from Chile039s Puyehue-Cordon Caulle chain volcano near the Cardenal Samore border pass between Argentina and Chile.
People gather on a road covered with pumice rocks from Chile's Puyehue-Cordon Caulle chain volcano near the Cardenal Samore border pass between Argentina and Chile. Reuters
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