Unresolved questions linger, after a sighting of a man possibly carrying a gun by three teenage girls, led to a massive, precautionary reaction by Virginia Tech and law enforcement on Thursday.

WASHINGTON, D.C. (WAVY) — The deadliest school shooting in American history occurred at Virginia Tech on April 16, 2007. On its 19th anniversary, Senators Mark Warner and Tim Kaine (both D-Va.) ...