Hundreds of new fires have flared up in the Amazon in Brazil, data showed Monday, even as military aircraft dumped water over hard-hit areas and G7 nations pledged to help combat the blazes.
Smoke choked Port Velho city as fires raged in the northwestern state of Rondonia where fire-fighting efforts are concentrated, amid a growing global uproar and a diplomatic spat between France and Brazil.
Two C-130 Hercules aircraft carrying thousands of liters of water on Sunday began dousing fires devouring chunks of the world's largest rainforest, which is seen as crucial to keeping climate change in check.
Swaths of the remote region have been scorched by the worst fires in years, sending thick smoke billowing into the sky.
Experts say increased land clearing during the months-long dry season to make way for crops or grazing has aggravated the problem this year.
Brazil's President Jair Bolsonaro has ordered an investigation into reports that rural producers in the northern state of Para held a "day of fire" on August 10 in a show of support for the far-right leader's efforts to weaken environmental protection monitoring in the region.
The worsening crisis has fueled a row between Bolsonaro and his French counterpart Emmanuel Macron, who has been piling pressure on the Brazilian leader to do more to protect the forest.
Seven states, including Rondonia, have requested the Brazilian Army's help in the Amazon, where more than 43,000 troops have been made available to combat fires.
It is not clear how many of them are actually involved in fire-fighting efforts so far.
After initially blaming the fires on non-government organizations, Bolsonaro on Friday vowed a "zero tolerance" approach to criminal activities in the Amazon and promised strong action to control the blazes.
Bolsonaro's delayed response came as the Amazon crisis threatened to torpedo a massive trade agreement between the European Union and South American countries, including Brazil, which had alarmed the powerful agriculture sector.
Dozens of firefighters arrived in Porto Velho on Sunday and Justice Minister Sergio Moro has given the green light for the deployment of security forces to tackle illegal deforestation.
The latest official figures show 80,626 forest fires have been recorded in Brazil this year, the highest number of any year since at least 2013.