Transcript for Italian police investigate what triggered a dangerous stampede at a soccer stadium

Back now with our "Index." With Europe on edge, police in northern Italy investigating what triggered this terrifying moment caught on camera. A dangerous stampede. Some 1,500 people injured when soccer fans packing a main square in turin panicked. Police say a loud firecracker may have set those fans off. This incident unfolding just about a half hour before the London terror attacks. And the New York City policeman dragged for nearly three blocks through the streets of Brooklyn. That officer was questioning the driver of a Honda sedan, when that car suddenly sped off. Dragging the policeman, who managed to fire off two shots, hitting a 15-year-old suspect in the face. Both the officer and teenager in critical condition tonight. That officer, a nine-year veteran with a wife and a 2-year-oldpdaughter. And now to the superhero shattering box office records this weekend. "Wonder woman," starring gal gadot. Outmuscling the competition, more than $100 million in its debut. The biggest blockbuster ever directed by a woman, Patty Jenkins.

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