Violence returned to protests against Nicaraguan President Daniel Ortega when riot police confronted students who had seized a university.
Students demanding greater democracy and Ortega's resignation took over the Engineering University in Managua, the capital.
Government supporters moved to end the takeover, but anti-government protesters took the students' side. The opposition demonstrators then partially set fire to the pro-government radio station Radio Ya, whose offices are located near the university.
Police were sent to contain the protests Monday and there were reports of people injured.
Protests erupted in mid-April after Ortega imposed austerity measures for Nicaragua's social security system. At least 76 people died amid a violent response from police and government-allied Sandinista youth groups.