PARIS—Authorities in France and Belgium on Thursday banned road blockades threatened by groups organizing online against COVID-19 restrictions, in part inspired by protesters in Canada. Citing “risks of trouble to public order,” the Paris police department banned protests aimed at “blocking the capital” from Friday through Monday. Police will put measures in place to protect roads and detain violators. Blocking traffic can lead to two years in prison, 4,500 euros (more than $5,000) in fines, and a suspended driver’s license, the police department said in a statement. Online chat groups in France have been calling for drivers to converge on Paris starting Friday night, and to continue north to Brussels on Monday. There have been calls to action in Belgium for truckers to converge on the capital, which houses European Union institutions. Authorities in Belgium banned Monday’s threatened blockade, and said a wide perimeter around the city of 1.1 million …