This photograph shows a plume of smoke rising into the sky during a wildfire in the Hautes Fagnes (High Fens) nature reserve in Lontzen. AFP
Firefighter reinforcements from all of Belgium and from Germany have been called in to help tackle the blaze, which ballooned in size overnight, with water bomber aircraft and helicopters also mobilised under the EU's Civil Protection Mechanism.
The nearby village of Sourbrodt, with about 500 residents, was under threat of evacuation.
"It is under consideration because of the smoke, but no final decision has been taken yet," Nicolas Yernaux, a spokesperson for the regional authorities in Wallonia told AFP.
"There is a risk that the fire could reach homes, but we are deploying all available resources to protect them," he added.
In Eupen, a municipality close to the fire, the sky was gradually turning yellow, with columns of smoke visible in the distance, according to an AFP journalist at the scene.
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