UN Secretary-General Antonio Guterres said yesterday that he was “deeply concerned” by wildfires that have devoured large sections of the Amazon rainforest, blanketing several Brazilian cities in thick smoke.

The Secretary-General tweeted that in the midst of the global climate crisis, we cannot afford more damage to a major source of oxygen and biodiversity. He further said the Amazon must be protected.

The extent of the area damaged by fires has yet to be determined but smoke has choked Sao Paulo and several other Brazilian cities. Forest fires tend to intensify during the dry season, which usually ends in late October or early November.