https://www.reddit.com/r/rpg/comments/6hc7lt/a_journalist_managed_to_foia_the_fbi_file_for/
"Tell us about FRESNO!"
Gygax rolls dice, checks result
"No!"
Apparently it was part of their investigation of the Unabomber. He had contacts in tabletop war gaming, so basically they investigated all the war gamers, to see if they were plotting an uprising against the federal government.