Hundreds of volunteer firefighters work 12 to 18 hours a day fighting forest fires near central Chile's Santa Juana commune, one of the areas most affected by the devastating, drought-fueled forest fires.

International experts Monday joined Chile's frantic fight against devastating, drought-fueled forest fires that have killed 26 people, injured hundreds and destroyed more than 1,100 homes in less than a week.

Officials said the blazes in south-central Chile, some 280 of which were still burning Monday, have consumed about 667,000 acres of land -- an area larger than the country of Luxembourg.

As the alarm was raised over a new surge in temperatures starting Tuesday after a brief reprieve, a DC-10 air tanker from the United States arrived in the country to join the battle by some 5,600 firefighters against 69 of the highest priority fires.

The craft is capable of dropping 36,000 liters of water.

Chile's SENAPRED emergency response service said the fires have left 1,260 people injured and another 3,000 without homes.

At least one firefighter was among the 26 dead, and eight among the injured.

Aid volunteer Carmen Cuevas told AFP of seeing parts of her hometown of Santa Juana in the hard-hit Biobio region, some 500 kilometers south of the capital Santiago, "turned to ash," as she helped Monday to distribute water to affected people.

Interior Minister Carolina Toha told reporters that in five days of fires, an area was destroyed equivalent to "what is usually burned in two years of fires."

Over the weekend, the minister said Chile was becoming one of the countries most vulnerable to fires due to climate change.

Fire conditions that would have seemed extreme just three years ago are becoming more common, she said.

Chile is experiencing a summer with record temperatures that have repeatedly exceeded 40 degrees Celsius in areas where this has historically been rare.

Sunday, a plane arrived from Spain with 50 firefighting experts, soldiers and drone pilots to aid in the massive containment operation.

Argentina promised some 60 firefighters as well as trucks and a helicopter, while a contingent of 150 military and civilian specialists arrived from Mexico.

France's President Emmanuel Macron sent a message of support on Twitter, saying: "The Chilean people can count on the support of France to fight against this catastrophe," while Portugal said it was ready to send 140 firefighters.

According to Chile's foreign ministry, Ecuador, Colombia, Peru, Paraguay and Venezuela have also pledged aid.

"It is wonderful to see how other countries that have their own problems and needs, are allocating their resources to help us right now," Toha said in a message of thanks.