Firefighters raced Tuesday to contain a massive blaze that ravaged a national park in the Brazilian capital, which has been suffering from a heatwave and more than four months of drought.

The fire that hit the park on Monday burned about 2,000 hectares (nearly 5,000 acres) of the 42,000-hectare reserve in Brasilia, according to national park service ICMBio.

Forty firefighters from ICMBio and the Brasilia Fire Department managed to bring one of the two fronts of the fire under control Monday night.

The fire is concentrated in an area about 30 kilometers (19 miles) from the presidential offices, the Planalto Palace.

“Severe conditions,” including temperatures exceeding 30 degrees Celsius (86 Fahrenheit) and critically low humidity levels of about 30 percent, have exacerbated the already inflammatory situation the drought has left in its wake, ICMBio said.

It hasn’t rained in the Brazilian capital for 122 days.

Officials said they don’t yet know what caused the fire.

Brasilia National Park was established in 1961, a year after the inauguration of the ultra-modern capital of central western Brazil – a region with a prolonged dry season that typically lasts from May to September.

The Brasilia fire comes as officials report an alarming increase in fires in the Brazilian Amazon.

Last month was the worst August in 12 years, with 33,116 fires detected in Brazil’s share of the world’s largest rainforest, according to satellite monitoring by the national space agency INPE.

President Jair Bolsonaro, who is up for re-election in October, has faced international outcry over a wave of fire and destruction in the Amazon, whose billions of carbon-absorbing trees are a major buffer against global warming.