Officials tell NBC Charlotte that 22 people were injured in the collapse of a concrete-covered area on the campus of North Iredell High School.The Sheriff’s Office confirmed that a concrete-covered area collapsed on the campus of North Iredell High School Saturday afternoon after a large truck backed into the structure.Authorities say there were students on campus at the time of the collapse, and there are multiple injuries, however the extent of injuries and whether the injured parties are students or not is not yet known.