Did you ever wonder what happened today in history?
There are resources (in our library) that list dates and events.
One resource is: The Encyclopedia of American Facts and Dates (E 174.5 C3 1987). On May 4, 1970 "At Kent State University in Kent, Ohio, four students were killed when National Guard troops fired at some 600 antiwar demonstrators, some of whom had been throwing rocks at the guardsmen and taunting them."
Another resource is: 2005 Chase's Calendar of Events (GT 4803 C48 2005) "May 4, 1970. Four students (Allison Krause, 19; Sandra Lee Scheuer, 20; Jeffrey Glenn Miller, 20 and William K. Schroeder, 19) were killed by the National Guard during demonstrations against the Vietnam War at Kent (Ohio) State University."
18 years between the resources and they tell the same story but just a little differently.