Authorities in central Colombia are on heightened alert after an increase in seismic activity in the Nevado del Ruiz volcano.
According to the Volcanological and Seismological Observatory in the city of Manizales — only miles away from the volcano, the volcano caused a minor M3.1 earthquake early Monday morning
One the day of May 6 at 2:55 local time a volcanic-tectonic earthquake with a magnitude of 3.1, associated with the fracturing of rock within the volcano, was registered at the northeast of the Arenas crater, at a depth of 3.59 kilometers (2.2 miles).
The volcano has shown heightened seismic activity for weeks; in April ash clouds came down on nearby towns
The Nevado del Ruiz, a hulking 17,457 ft volcano straddling the border of the Caldas and Tolima departments, is the most observed volcano in the country. The volcano took the world stage in 1985 when a tragic eruption destroyed Armero, claiming an estimated 25,000 lives.