A weekend of intense, sometimes violent nationwide protests culminated in the arrest of hundreds of demonstrators, angry at the latest killings of black men by police officers.
Despite pleas for calm from all sides, at least 312 people have been arrested at protests from New York to Chicago, and in St. Paul, Minnesota, and Baton Rouge, Louisiana, where two black men, Philando Castile and Alton Sterling, were shot to death by police.
The same week Sterling and Castile were killed, a gunman killed five police officers at a Black Lives Matter rally in Dallas.
Their killer was an Afghanistan war veteran, 25-year-old Micah Xavier Johnson from the Dallas suburb of Mesquite, Texas.
Black Lives Matter protesters condemned the Dallas killings, calling the attack on law enforcement a tragedy not just for those affected but also for the nation.
Authorities, protest leaders and the mother of one of the victims have appealed for calm as over 300 demonstrators, angry at the latest killings of black men by police officers, were arrested in a weekend of intense, sometimes violent nationwide protests.
Police departments across the United States are searching for new tactics for a more difficult era of racial tension, increasingly lethal mass shootings and global terrorism.