Hundreds of Colombian prisoners have been expelled by Ecuador to relieve prison congestion, sparking outrage from the authorities in Bogota, who have described the operation as unilateral. The expulsions took place without warning, surprising the Colombian authorities, who were not prepared to receive them. Ecuador justifies the measure as a way to reduce violence in prisons, where gang clashes have led to many deaths. Colombia's diplomatic response was firm, protesting the Ecuadorian action.