Volcano in Ecuador spews huge column of ash.

QUITO, Ecuador - A volcano in Ecuador that has not erupted in nearly 140 years belched a column of ash eight kilometers high on Friday, prompting officials to raise the alert level.

In addition to the five-mile plume, several explosions erupted in the course of the day, the Geophysics Institute said.

The Cotopaxi volcano stands 5,897 meters high and is 45 kilometers south of the capital Quito.

Orders have already been given for a million surgical masks to be distributed across the city of 2.3 million, Mayor Mauricio Rodas said.

The Geophysics Institute said Cotopaxi is one of the most dangerous volcanoes in the world because of the large amount of snow at its peak and because nearby areas are densely populated.

The last time it erupted was in 1877.

The government's emergency management agency raised the alert level in areas near the volcano to yellow, which is in the middle of the scale.

The Environment Ministry declared the volcano off limits to tourists. Fifteen climbers who were preparing to scale the mountain were sent home.

CAPTION(S):

View of the Cotopaxi volcano spewing ashes in Pichincha province, Ecuador on August 14, 2015. The volcano spewed a column of ash five kilometers high on Friday, prompting officials to raise the alert level. AFP PHOTO / JUAN CEVALLOS