A series of powerful eruptions of Guatemala's Volcano of Fire blanketed villages in dense clouds of ash, and prompted evacuation orders for over 33,000 people.
The massive columns of smoke from the volcano could be seen from the capital, some 75 kilometers (50 miles) away, and motorists said they saw a huge cloud of ash coming down slopes.
"This type of eruption is stronger than normal and hasn't been seen in recent years. That's why we have declared an orange alert" in the area around the volcano, in western Guatemala, Gustavo Chigna of the National Institute for Seismology, Volcanology, Meteorology and Hydrology told local media.
He said the eruption had buried several villages in ash near the 3,763-meter (12,345-foot) tall volcano. Rumbling could be heard for several kilometers around.
Javier Garcia from the village of El Porvenir told local radio that he had initially planned to stay put.
But after seeing "the great eruption and all the ash that was falling, we decided to seek refuge," he said. "Everything went black and we could not breathe."
Families were being evacuated in sugar mill buses and trucks normally used to transport goods and cattle, Mariano Lam, a spokesman for volunteer firefighters, told AFP.
But he complained that many people were reluctant to leave their homes and decided to "stay at their own risk."
The national disaster reduction agency CONRED has set up a command post in the nearby municipality of San Juan Alotenango in Sacatepequez department, to coordinate care for the affected population.
Six communities in Yepocapa and another in San Juan Alotenango are the most affected, according to CONRED.
Moderate to strong explosions have been shaking the volcano, sending debris up to 3,000 meters above the crater and forming thick columns of ash spreading to the west and northwest, according to the volcanology institute.
Further complicating the picture, heavy rains were reported in areas near the volcano, prompting CONRED to take "preventive measures" on different roads and at riverbeds.