Brazil's government told ranchers and farmers on Friday to stop setting fires in the Amazon rainforest as clouds of dense gray smoke make the air increasingly unbreathable in the northern city of Manaus, threatening sanctions if they do burn areas of land.

"Fire is not natural in the Amazon, it comes from criminal actions or deforestation," Environment Minister Marina Silva told reporters. "There are people criminally setting fire to public and private areas."

The world's largest rainforest is facing a historical drought worsened by the El Niño weather phenomenon. Rainfall below average is increasing the polluting effects of the region's annual burning season.

This is the time of the year when fires tend to spike in the Amazon as rain subsides, making it easier for ranchers and farmers who use fires to clear land, raise cattle and grow commercial crops.

According to the Brazilian government, 60 of the 62 cities in northern Amazonas, the Brazilian state with the biggest indigenous population, have declared a state of emergency because of drought and wildfires, and the month of October is expected to be "challenging."

Silva said the government would send more than 300 firefighters and two aircrafts to help put out the fires.

Those who deliberately set fire to private areas will have their properties embargoed and no longer be able to obtain funding, according to Rodrigo Agostinho, the head of the Brazilian Institute of Environment and Renewable Natural Resources under the Ministry of Environment.

President Luiz Inacio Lula da Silva has staked his international reputation on reversing environmental back-sliding under his far-right predecessor, Jair Bolsonaro, when Amazon deforestation soared.

In the first nine months of 2023, deforestation in the region fell by 49.5 percent on a yearly basis, according to preliminary data from the space research agency National Institute for Space Research.

"If we hadn't reduced deforestation by almost 50 percent we would be living through the Apocalypse," Silva said. "Right now we're in a climate emergency in Brazil."