Two lakes in a remote coastal region of Patagonia in Argentina have turned fluorescent pink, an as yet unexplained phenomenon that local environmentalists fear may be harmful and caused by industrial pollution.
The lake, located next to an industrial park on the outskirts of the Argentine city of Trelew, stretches over dusty desert plains.
Local and regional environmental authorities are investigating the causes and possible damage to the lake, but have not yet reached a conclusion.
