How U.S. I-Day parade turned into 'warzone'; Shooter unleashed AR-15 in Chicago

It was the morning of the U.S. Independence Day Parade celebration for a Chicago suburb when suddenly dozens of bullets were fired, followed by chaos in the streets amid screams. It was at this moment, when 22-year-old Robert Crimo opened fire at the crowd from a rooftop with his AR-15. He was arrested later after hours of manhunt. 6 people died and at least 80 others were injured in the mass shooting, including kids. One of the clips, which is particularly disturbing, captures the moment when the attacker opened fire from a rooftop. People ran in all directions, seeking shelter, and teens - on bicycles - could not understand what was happening. Watch this video for more details.