Open this photo in gallery: Several hundred students and pro-Palestinian supporters rally at the intersection in front of Woolsey Hall on the campus of Yale University, in New Haven, Conn., on April 22.Ned Gerard/The Associated Press Police arrested dozens of people at a pro-Palestinian demonstration at Yale University on Monday, hours after Columbia University canceled in-person classes in response to protesters setting up tent encampments at its New York City campus last week. Demonstrators blocked traffic around Yale’s campus in New Haven, Connecticut, demanding the school divest from military weapons manufacturers, video footage aired on social media showed. Police arrested...