A minimum of six firefighters have left fighting a blaze inside a mountain forest in southern Chile, the government bodies say.
Two others were badly burned within the fire within the Araucania region.
In the last week multiple forest fires have ravaged large regions of central and southern Chile.
Leader Sebastian Pinera states in newspaper headlines some have been began deliberately, and it has invoked an anti-terrorist law to pursue anybody responsible.
The six volunteer firefighters who died were a part of an organization attempting to extinguish a blaze near Carahue within the Araucania region, about 700km (434 miles) south from the capital Santiago.
Mr Pinera didn't say who he thought may be responsible.
Recently Araucania has seen protests by indigenous Mapuche activists who say their ancestral lands happen to be absorbed by forestry companies.
Some happen to be punished for alleged arson using anti-terrorist laws and regulations. Mapuche activists have blamed forestry companies for that fires.
Too as with Araucania, there are also recent wildfires within the Bio Bio region, further north, as well as in Torres del Paine National Park in Patagonia within the far south.