Black Hate Groups/online radicalism

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Black Hate Groups/online radicalism

The online wanderings of Micah Johnson show a man drawn to black nationalist symbolism. Drew Griffin reports.

03:42 - Source: CNN

Dallas Police Officers Shot 37 videos

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Black Hate Groups/online radicalism

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CNN's Sara Sidner shows you what a pound of C-4 on a robot arm does in light of the Dallas Police tactic against a sniper.

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DALLAS, TX - July 8, 2016: Dallas Mayor Mike Rawlings (R) looks on during a press conference at Dallas City Hall as Dallas Police Chief David Brown speaks on the fatal shootings of five police officers on July 8, 2016 in Dallas, Texas. At least one sniper killed five officers and wounded seven others in a coordinated ambush at a anti-police brutality demonstration in Dallas. The sniper was killed, and three other people are in custody, officials said. (Photo by Stewart F. House/Getty Images)

Dallas police chief praises officers during shootings

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Dallas Mayor Mike Rawlings says they believe Dallas police shooter Micah Xavier Johnson acted alone

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Dallas Police respond after shots were fired at a Black Lives Matter rally in downtown Dallas on Thursday, July 7, 2016. Dallas protestors rallied in the aftermath of the killing of Alton Sterling by police officers in Baton Rouge, La. and Philando Castile, who was killed by police less than 48 hours later in Minnesota. (Smiley N. Pool/The Dallas Morning News) -- MANDATORY CREDIT, NO SALES, MAGS OUT, TV OUT, INTERNET USE BY AP MEMBERS ONLY

Chaos in Dallas as 12 officers are shot

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TOPSHOT - Bystanders stand near pollice baracades following the sniper shooting in Dallas on July 7, 2016.
A fourth police officer was killed and two suspected snipers were in custody after a protest late Thursday against police brutality in Dallas, authorities said. One suspect had turned himself in and another who was in a shootout with SWAT officers was also in custody, the Dallas Police Department tweeted.
/ AFP / Laura Buckman (Photo credit should read LAURA BUCKMAN/AFP/Getty Images)

Police: Suspect said he wanted to kill white officers

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A Dallas police officer, who did not want to be identified, takes a moment as she guards an intersection in the early morning after a shooting in downtown Dallas, Friday, July 8, 2016. At least two snipers opened fire on police officers during protests in Dallas on Thursday night; some of the officers were killed, police said.

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People rally in Dallas, Texas, on Thursday, July 7, 2016 to protest the deaths of Alton Sterling and Philando Castile.
Black motorist Philando Castile, 32, a school cafeteria worker, was shot at close range by a Minnesota cop and seen bleeding to death in a graphic video shot by his girlfriend that went viral Thursday, the second fatal police shooting to rock America in as many days. / AFP / Laura Buckman (Photo credit should read LAURA BUCKMAN/AFP/Getty Images)

'It looked like an execution'

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Police: Suspect said he's going to kill more

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Dallas shooting witness: I heard about 20 gunshots

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