Two lanes on the Antwerp ring road towards the Netherlands were closed on Monday afternoon near the AFAS Dome after a truck had spilt its load, according to the Flemish Traffic Centre.
A truck with an open trailer lost an unknown sludge-like substance, possibly containing potatoes, when it had to brake sharply due to traffic congestion.
Firefighters are working to clear the mess from the road, but progress is slow. The location is a traffic bottleneck, causing severe disruption, says Peter Bruyninckx of the Traffic Centre.
Queues now extend to the E313 and just before the Kennedy Tunnel, with delays exceeding an hour.
The truck continued driving after losing its load and is still being tracked down.
