Florida school shooting suspect's disturbing social media posts

Nikolas Cruz, described as a loner by a former classmate, had once been expelled from a Parkland, Florida, high school for disciplinary reasons. On Wednesday, the 19-year-old former student returned to Marjory Stoneman Douglas High School and is suspected of gunning down at least 17 people, in a massacre that has now become one of the 10 deadliest mass shootings in modern US history.