Around 10 ducks have been found dead in one of the ponds at Bois de la Cambre, and the City of Brussels suspects a bacterial outbreak.
Sudinfo reports that samples from the water have been taken to lab to be analysed, and results are expected in the coming days. But the city is already suspecting botulism, a bacterial disease that can develop in warm water during periods of prolonged heat.
Workers are removing the dead birds and keeping a close eye on the ponds.
People have reportedly been dipping their toes in the Bois de La Cambre's ponds to cool off during this week's heatwave, but the City has reminded members of the public not to swim in the ponds, as the waters are unsafe.
Brussels Councillor for green spaces, Florence Frelinx, told Sudinfo: "These ponds are not swimming areas. During a heatwave, bacteria can multiply more easily and pose a risk to both people and wildlife."
The councillor also warned dog owners to keep their pets away from the waters until the results are out.
The city reportedly said it will continue monitoring the ponds and will provide an update once the laboratory analyses have been completed.
