An unarmed security monitor in a golf cart was the first person to see Nikolas Cruz step out of an Uber, a large bag in hand, and stride toward Building 12 at Marjory Stoneman Douglas High just before the worst school shooting in state history. Cruz, however, was no stranger to staff. "Nikolas Cruz. I knew the kid," security guard Andrew Medina told Broward detectives in a sworn video-recorded statement released by prosecutors on Tuesday evening. As soon as Cruz began walking "like on a mission" toward the building, Medina followed and began frantically texting fellow security guards. "We had...