Violent confrontations left six people dead and at least 100 injured Sunday as teachers in Mexico began protesting mandatory testing—part of the country’s sweeping education overhaul. The members of the radical teachers’ union and anti-riot police clashed as officials attempted to move protesters who were blocking a highway. Protesters reportedly threw stones and Molotov cocktails. Associated Press journalists reported that police fired on protesters. The National Coordinator of Education Workers say they are protesting against the mandatory testing of teachers as well as the arrests of union leaders on money-laundering charges. Fifty-three civilians, 41 federal officials, and 14 local authorities were injured in the exchanges.