Strasbourg, France ? Demonstrators fought with police and smashed windows at the European Parliament building Monday during a protest over a proposal to make port operations in the European Union more competitive.

Strikes and work slowdowns also disrupted cargo handling at several ports as unions pressed their opposition to the plan even as EU legislators predicted it would be rejected.

Police used water cannons and tear gas trying to keep thousands of protesters away from the EU legislature in this eastern French city. But the mob surged forward, hurling rocks, logs and metal fences to shatter windows along a 150-foot stretch of the building’s front.

Earlier, officers fired pepper gas into a crowd of protesting dock workers from major European ports who threw flares, glasses and stones at officers. At least three protesters were detained.

Workers in yellow vests accompanied by marching bands set off smoke bombs and waved banners saying “Victory to the dockers.” Some cars were set afire, and smoke mingled with the smell of pepper spray in parts of the old town.

At the same time, workers went on strike at Antwerp, Belgium – Europe’s second biggest port – and in Portugal and Denmark. Dockers staged short work stoppages in Sweden and at Europe’s biggest port, Rotterdam, Netherlands.

They are angry over the resubmission of a port liberalization bill by the European Commission, the EU’s administrative body.

The commission wants more competition in cargo handling, ending the situation at many European ports where loading and unloading is run by monopoly handlers. Supporters say that would cut costs at ports that often must be subsidized by governments.

Unions fear the proposal would mean less jobs and lower wages, while cargo-handling companies worry they might lose contracts to competitors.

The proposal previously was rejected by the European Parliament in November 2003, and the same result was expected in a vote set for Wednesday.

Center-left parties oppose the legislation, and even the conservative European People’s Party is split on the issue.

Georg Jarzembowski, the conservative German lawmaker steering the legislation through the assembly, said there was little chance it would pass.