Wildfires burned in the Brazilian most populous state of Sao Paulo all weekend, causing plumes of smoke in the sky, with authorities declaring a "war against the fire."

Fires spread through southeastern Brazil, with Sao Paulo governor Tarcisio de Freitas decreeing a state of emergency in 45 municipalities. He said two people suspected of starting fires had been arrested.

Fires burned through sugarcane fields and local media showed several dead cattle that had succumbed to the smoke and heat.

Roads, schools closed

The fires caused transport disruptions. Authorities closed some highways due to lack of visibility. A Brazilian championship football match was also canceled in Ribeirao Preto city.

In Sao Jose do Rio Preto, more than 300 fires have been detected, forcing authorities to close schools.

"Fires emit dense and toxic smoke that harms the environment and human health, causing problems to the respiratory system and cardiovascular disorders," a government statement said.

"So far we have not detected any fire caused by lightning, which means there are people starting fires," Brazilian President Luiz Inacio Lula da Silva said on X, formerly Twitter.

The state government has placed 36 cities on "high alert" due to the fire. 

"We are chartering planes to spray water in addition to fire department aircraft," Sao Paulo Governor Tarcisio de Freitas told the media.

Two factory workers died in the Urupes municipality while fighting flames.

Hot dry weather

Brazil is currently at the peak of its dry, hot season. Low humidity and high temperatures have led to an increase in fires in the southeast, which is also experiencing drought conditions.

This year, the wildfire season started early in May in Pantanal, the world's largest wetlands.

According to government data, the number of fires in the Amazon rainforest was at a two-decade high in July.

Extreme weather has deeply affected Brazil, also causing rare flooding in the state of Rio Grande do Sul that left more than 170 dead.

tg/rmt (AFP, Reuters)