At least 312 people were killed by the Aug. 10 quake, according to figures published Wednesday by the central government, and 29,000 homes were destroyed.
Aid agencies consider the first 48 to 72 hours crucial for retrieving survivors, though that threshold can be extended if they have access to food and water.
Water and some food items were already running short in supermarkets and shops. Almost all of Pereira was left without electricity, and the cell network is patchy at best.
Colombia’s Geological Service said Monday's quake was the country's strongest recorded “in the 21st century,” and that it was followed by several aftershocks.
