Fire and large clouds of gas and ash spew from the mouth of Ecuador's Tungurahua volcano, 84 miles (135 kilometers) southeast of the capital city of Quito.
The 16,475-foot (5,023-meter) volcano has been erupting intermittently since October 1999, but more aggressive activity prompted the authorities to raise the security alert from "moderate" to "high" this week.
Ecuadorean authorities told the Associated Press that more than a hundred families have been evacuated from the vicinity of Tungurahua—which means "throat of fire" in the region’s indigenous Quechua language.
Carlos Sanchez analyzes samples of volcanic ash from Tungurahua in Baños, Ecuador, on August 21, 2012.
Sanchez, 70, calls himself the “Volcano Watcher" because he helps volcanologists by observing Tungurahua from a tree house that is located less than a mile from the volcano's crater.
History Repeats Itself?
Dense clouds of volcanic gas and ash billow from the mouth of Ecuador's Tungurahua volcano this week, during a period of heightened activity that caused authorities to raise the security alert from "moderate" to "high."
Eruptions in 2006 killed at least four people, left two missing, and forced the evacuation of thousands of people, according to the Associated Press.