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FBI begins 'terrorism investigation' in Chattanooga
CNN's Victor Blackwell reports on the aftermath of the Chattanooga shootings and the FBI investigation.
02:29 - Source: CNN
Chattanooga shooting 28 videos
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FBI begins 'terrorism investigation' in Chattanooga
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Marines 'willingly ran back into the fight'
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Chattanooga shooter followed writings of al Qaeda cleric
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Sources: Shooter searched 'martyrdom' online
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White House, U.S. Capitol flags lowered to half-mast
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Armed man stands guard at recruitment center
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Family spokesman: Chattanooga shooter had depression
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Mohammad Youssuf Abdulazeez is the suspected gunman in July 16, 2015 Chattanooga, Tennessee Naval Reserve shooting that left four Marines dead and the gunmen also killed.
What did the shooter's writings reveal?
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A police car blocks the entrances to the Tennessee Naval Reserve Center on Thursday July 16 in Chattanooga, Tennessee. Authorities say Mohammod Youssuf Abdulazeez, 24, opened fire first on a military recruiting station at a strip mall and then moved to an operational support center operated by the U.S. Navy seven miles away, where he killed four U.S. Marines.   The gunman was also killed.
States increase security for military installations
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How the Chattanooga shooting unfolded
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Witness records gunfire during Chattanooga shooting
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Investigators look for clues about Chattanooga gunman
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Chief: Wounded cop dragged 'from under the gunfire'
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Mohammod Youssuf Abdulazeez's mugshot from 4/20/2015
Chattanooga shooter's father was investigated by FBI
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Mayor: We had no indication shooter was a threat
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Marine killed in Chattanooga shooting identified
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FBI: We are checking every lead
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Muslim community condemns Chattanooga shooting
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Friend of shooter: 'It's a wave of disbelief and shock'
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MMA coach: He was an All-American kid
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Chattanooga mayor: Our hearts are breaking
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What do we know about Mohammad Youssuf Abdulazeez?
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Video: Chattanooga shooter participated in MMA fights
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Vehicle used in Chattanooga shooting a rental
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Mohammod Youssuf Abdulazeez
Coach: Chattanooga shooter was 'humble' and 'smart'
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4 Marines killed in Chattanooga shooting attack
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Obama: Chattanooga shooting a 'heartbreaking circumstance'
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Witness: 'I was in shock at how many times he fired'
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