In a haze of ash, Chileans navigate a road in the town of Futaleufz on May 5. Authorities began a second round of evacuations Monday as Chaitin continued erupting.

The peak has been spitting some lava, but the main concern is a possible blast of pyroclastic flowa superheated, fast-moving, low-lying mix of toxic gas and ash.

"Lava flow would not reach Chaitin [city], but hot fragments, ash, and gas could," government geologist Luis Lara told the Reuters news service.

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