Update 4:20 P.M.
D.C. police say a Holocaust Museum guard, Stephen Tyrone Johns, and the alleged shooter, James von Brunn, were rushed to George Washington University Hospital.
Police have now confirmed that Johns has died.
Grace Mann, a student at The University of Mary Washington, was found unconscious Friday in her Virginia home
Iona Costello and her teenage daughter, Emily, were missing for three weeks after going to Manhattan for a vacation