When they heard a fire alarm sound, the superintendent dispatched Earl Metcalf to see what the problem was at the 3rd floor.
He met Joe Kosidlo, the 3rd floor custodian, who asked him to vacate because he thought he heard gun shots.
At this time there were no students present and only Principal Louis Nicol, secretaries, business office, maintenance and custodians were at the school.
By 5:20 p.m., local and State Police officers were surrounding the school building,[6] and a National Guard tank had arrived to remove the injured victims.
[12][13] Barbaro was laid onto a stretcher and transported by ambulance to the hospital, examined and, having suffered no injuries, was then transferred to the Olean City Jail.
[1][6][12] Those killed were Earl Metcalf, Neal Pilon, and Carmen Wright Drayton, who was six months pregnant.
Seven people survived the shooting with gunshot wounds, while four others sustained injuries from flying glass fragments.
[1][6][13][17] He ranked eighth highest academic score in his senior class,[2][16] and was inducted into the National Honor Society in February 1974.
[10][12][14][16] Barbaro lived in Olean, New York, with his parents and his three younger siblings – sister Cecile, brothers Steven and Chris.
[17] His father was an executive of a successful manufacturing firm,[10] while Anthony worked with his mother at a local fast-food restaurant.
In a note explaining his motives, Barbaro wrote: I guess I just wanted to kill the person I hate most -- myself, I just didn't have the courage.
[11] Following the shooting, police had found homemade smoke bombs, as well as gasoline and glass bottles, and empty propane canisters in Barbaro's bedroom.
Police also found, in Barbaro's bedroom, bomb recipes and a journal that detailed his plans for the shooting.
[5][19] In April 1975, he had entered a plea of not guilty by reason of insanity,[8] however he was found competent to stand trial by two court-appointed psychiatrists.