The Nevado del Ruiz volcano, whose eruption 26 years ago killed around 25,000 people, is showing signs of activity after nearly 20 years laying dormant, said Colombian geological group Ingeominas Thursday.
Early Friday morning, geologists completed an observational fly-over with the assistance of the Colombian Air Force, during which they photographed the Nevado del Ruiz volcano and noted “ash on the glacier, near the crater rim and on the eastern flank,” as well as a 4,500 foot gas column at the mouth of the volcano. During the same day a seismic tremor was reported along with an increase in sulfur dioxide emissions.
All of these factors signal that the volcano is heating up.
Located about 80 miles west of Bogota, Nevado del Ruiz is an active volcano that produces pyroclastic flows, or swift currents of hot gas and rock that lead to destructive mudslides. There have been numerous eruptions over the centuries, with the most recent was on November 13, 1985.