Seismic activity has increased at Nevado del Ruiz volcano in Colombia as authorities advise the community to remain calm.In the department of Caldas, according to the latest bulletin issued by the Colombian Geological Service( SGC), there is a seismicity increase inside the Nevado del Ruiz volcano, due to the activity of the lava dome. The Risk Management authorities in the region ensure that the yellow alert remains.... They have also called on the community not to generate false information.