Nationwide strikes in France intensified on Friday, as more students joined the protests, boycotting classes and blockading high schools and universities, the Associated Press reported. The country has been wracked by four days of outrage against President Nicolas Sarkozy’s proposed retirement reforms, which include raising the retirement age.  The reforms do not directly affect students, but the main French student unions, representing both high-school and university students, called for their members to join in the protests, affecting hundreds of lycées and several universities. The University of Rennes 2 was closed on Thursday for “security reasons” after the institution’s president said a vote by the university’s general assembly to block access to the university was “illegal,” according to EducPros, an education news site.