Firefighters in Oregon are battling a blaze inside one of the world’s tallest trees – the Doerner Fir – a coastal Douglas Fir standing over 325 feet tall and believed to be more than 450 years old, reported news agency AP.The fire, which began on Saturday in Coos County in Oregon’s coast range, has been burning inside the tree trunk about 280 feet above the ground. While an infrared drone flight on Tuesday showed no flames or smoke at the top, heat remains trapped within a cavity, according to Megan Harper, spokesperson for the federal bureau of land management (BLM).Crews have been working to determine how best to access the fire within the massive trunk. “Figuring out how to approach the tree from the side to douse the cavity with water has been a challenge,” Harper said, adding that options like building scaffolding or climbing adjacent trees are being considered, according to AP.Helicopter bucket drops had earlier reduced fire activity near the tree’s top, while sprinklers and containment lines had been set up at its base, as per the Coos forest protective association. A helicopter remains on standby for further water drops.The fire has already caused visible damage. “We’ve lost about 50 feet of it, just from fire and pieces falling out,” Harper confirmed. “So I don’t know where it’ll stand after this, but it’s still a magnificent tree,” as quoted by the agency.Though lightning has been ruled out as the cause, the exact origin of the fire remains under investigation. Notably, the Doerner Fir is the only tree burning in the immediate area, the BLM said.Despite the damage, officials believe the tree is not at immediate risk of total destruction. “The tree is so big, it’s got so much mass that it would take a while for it to burn all the way through,” Harper explained.Efforts to save the tree continue with urgency. “I think people really love it,” Harper said. “There’s a lot of history there, and so we don’t want to lose it.”