Several fire hotspots remained active in the Fagnes on Sunday morning, and residents evacuated from Waimes and Bütgenbach were still unable to return home.
Authorities said it was not yet possible to say when people would be allowed back, while around 20 evacuees spent the night at the sports hall in Malmedy.
Local and federal police continued to guard the evacuated neighbourhoods, according to the provincial governor, who said the defensive line protecting the affected areas was holding.
No homes had been damaged so far, the governor’s office said, but the fire remained close to residential areas and heavy smoke was still a concern.
Emergency operations continued without interruption for a second night on the ground.
More than 100 Belgian and German firefighters remained deployed, alongside about 70 police officers, around 20 Civil Protection staff, some 40 military personnel and about a dozen medical and psychosocial emergency workers.
The Walloon Region’s Department of Nature and Forests and farmers who came to assist the emergency services also remained fully engaged.
In total, more than 250 responders and around 50 vehicles from all services were mobilised overnight, the governor’s office said.
At daybreak, helicopters from the Belgian Federal Police and the Netherlands resumed operations.
The aircraft are considered the most effective way to tackle the flames because the fire front is difficult to reach using ground crews.
To allow helicopters to take on water, tourist activity on Lake Robertville has been strictly limited to the beach at Robertville-les-Bains, and no boats are allowed on the lake.
The governor again urged the public to stay away from the area and to obey roadblocks and police instructions.
