BRUSSELS — Tens of thousands of demonstrators descended upon Brussels on Tuesday to voice their opposition to Prime Minister Bart de Wever’s proposed austerity measures, leading to clashes with police and widespread disruptions. Belgian authorities resorted to tear gas to disperse the crowds, as minor skirmishes erupted between law enforcement and protesters. The demonstrators, armed with drums, horns, flares, and smoke bombs, chanted slogans against cuts to social welfare programs, crippling traffic in the capital and major transportation hubs. The protest, organized by Belgium’s three major trade unions, was accompanied by nationwide strikes targeting De Wever’s plans to reduce spending on pensions and healthcare. While organizers claimed over 150,000 participants, police estimated the crowd at 80,000. The Federal Planning Office of Belgium predicts the country’s budget deficit will surge to 6.5% of GDP by 2030, exacerbating economic challenges. De Wever, a Flemish nationalist who assumed office in February, has vowed to implement stringent fiscal measures to address these issues. The unrest underscores the growing public discontent with his administration’s policies.