Calbuco, which erupted without warning on Wednesday, was still puffing out ash and smoke on Friday, leading airlines to cancel flights from Argentine capital Buenos Aires, some 1,400 kilometers east. Calbuco, considered one of the most dangerous along Chile's chain of around 500 active volcanoes, erupted twice in 24 hours on Wednesday and Thursday.
Chilean Volcano Huffs and Puffs

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View of the Calbuco volcano in Puerto Varas, Chile, April 24, 2015.

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A woman holds a mask to her face as she stands with her belongings before evacuating the town of Ensenada, Chile after the Calbuco volcano erupted, April 23, 2015

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A boat is seen in a house backyard at Ensenada town which is covered with ashes from the Calbuco volcano near Puerto Varas city, April 23, 2015.

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Picture taken from behind a window in Bariloche, province of Rio Negro, Argentina, of an ash cloud from the Calbuco volcano in neighboring Chile, April 23, 2015. (Secretaria de Medios Rio Negro / Daniel Ortiz)