The Amazon River has seen its levels in Colombia reduced by as much as 90 percent, a government agency said Thursday, as South America faces a severe and widespread drought.

The river—the world’s biggest by volume and which also flows through parts of Brazil, Peru, Bolivia, Ecuador, Venezuela, Guyana, French Guiana and Suriname—has been hard hit by the drought that has seen wildfires spread across the continent.

“The water level has decreased between 80 and 90 percent in the last three months due to drought caused by climate change,” Colombia’s National Unit for Disaster Risk Management (UNGRD) said in a statement…