The tailbacks have since cleared and all the road tunnels on the inner ring road have reopened.
Monday morning’s action was the latest in a series of protests and work-to-rules staged by the country’s police officers in their ongoing dispute about pay, conditions and staffing levels.
Previously the Federal Police staged a work-to-rule at Brussel Airport that resulted in around 100 people missing their flights and 25 flights being delayed.
The unions are demanding extra staff to resolve pressure of work issues and a pay increase. The current strike notice runs until the New Year. On Monday morning police union representatives were invited in for talks at the office of the Federal Interior Minister Annelies Verlinden.