Moises Castillo / AP

Smoke rises from the Fuego volcano in Palin, Guatemala, on Thursday.

A Guatemalan volcano erupting Thursday for the sixth time this year triggered evacuations of several towns, with more than 33,000 expected to flee.

The Fuego volcano started spewing lava some 2,000 feet down two slopes, while ash flew two miles upwards. Ash was covering homes and buildings several miles away, the government's disaster agency said.

While Fuego had erupted five times earlier this year, one scientist in Guatemala said today's eruption was the biggest since 1999.

Seventeen towns with 33,000 people are in the precautionary evacuation zone, the country's emergency response director said. By midday, more than 10,000 had fled, officials said.

The volcano sits just 6 miles southwest of Antigua, a colonial city popular with tourists. Antigua was not in the evacuation zone.

Cinders spewing from the volcano were settling a half-inch thick in many places, government volcanologist Gustavo Chicna said.

Extremely hot gases were rolling down the sides of the volcano, which was entirely wreathed in ash and smoke.

The emergency agency warned that flights through the area could be affected.

There was a general orange alert, the second-highest level, but a red alert south and southeast of the mountain, where, Chicna said, "it's almost in total darkness" due to the ash and smoke.

Teresa Marroquin, a Guatemalan Red Cross coordinator, said the organization had set up 10 emergency shelters and was sending hygiene kits and water.

"There are lots of respiratory problems and eye problems," she said.

The Associated Press and Reuters contributed to this report.

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