Some 6,000 hectares of Biebrza National Park in northeastern Poland were ablaze on Wednesday, as more than 120 firefighters rushed to extinguish the flames. Biebrza is home to 59,000 hectares of wetlands, wildlife such as moose, beavers, and unique species of birds, and hiking trails.

"It is impossible to calculate the loss. This is a tragedy, it cannot be described. We may have to fight this fire for months," park employee Janina Agnieszka Zach, told Polish broadcaster TVN.

Environment Minister Michal Wos said that the fire, which began burning on Sunday, was likely caused by illegal grass burning - a method sometimes employed to clear swaths of dead grass.

"Fires in the Biebrza National Park break out every year, but such a large one has not been there for years. The situation is very serious," Wos said in a statement.

"The wind and the unique drought this year make it very difficult to put out the fire," the ministry added.

Sources: dpa, Reuters