Some boos for mayor at NYPD graduation

New York City Mayor Bill de Blasio received some boos and heckles Monday at a police graduation ceremony, the latest chapter in his tension-filled relationship with the nation's largest police force. The rift between de Blasio and much of the rank and file has grown considerably in recent weeks, and the leaders of the police union have blamed the mayor for fostering an anti-NYPD atmosphere they believe contributed to the ambush slayings of two officers.