IFRC said in a statement issued Saturday that if the dam bursts, devastating floods could affect those people, and the Colombian authorities have declared a high alert and ordered the evacuation of communities near the Cauca River.
The IFRC statement said that only 6,485 of the 120,000 people at high risk have been evacuated so far.
Walter Cotte, Regional Director for the Americas at the IFRC, said that this situation had been worsening for a number of days and now looks like it may be reaching a critical level.
"It is a priority to guarantee the orderly evacuation of people in the municipalities most at risk," Cotte said.
According to the IFRC statement, the Colombian Red Cross has more than 200 volunteers of various specialties ready to be deployed, and has put its search and rescue and medical staff on alert.
"We are preparing for the worst," the statement said.
The Colombian Red Cross is being supported by IFRC disaster response specialists in-country, who are preparing an Emergency Plan of Action and requesting resources from IFRC's Disaster Relief Emergency Fund.
IFRC is the world's largest humanitarian network, comprising 190 National Red Cross and Red Crescent Societies working to save lives and promote dignity around the world.
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