 The first mail bomb was sent in May 1978 to materials engineering professor Buckley Crist at Northwestern University . On May 25 , the package was found in a parking lot at the University of Illinois at Chicago , with Crist 's return address . The package was " returned " to Crist , but when Crist received the package , he noticed that it was not addressed in his own handwriting . Suspicious of a package he had not sent , he contacted campus police officer Terry Marker , who opened the package , which exploded immediately . Marker required medical assistance at Evanston Hospital for injuries to his left hand . 
