In 1979 I learned from Clark that he had received a call the day of the assassination from Bill Sullivan, one of Hoover’s other top assistants, who told him to make sure I did not see the communique from the D.C. field office about Oswald writing to the Soviet Embassy in Washington. Clark then told Howe to keep the communique — which had just arrived the day of the assassination — and any others concerning Mexico City from me. Howe knew I had already seen the communique that afternoon, but he decided to remove it and other related memos from my file drawer so I couldn’t see it again.
I wonder why the fbi didn't want hosty to know lho had written a letter to the ussr embassy in early Nov 1963. Looks like the fbi were trying to keep hosty in the dark for some reason. Perhaps they thought the less he knew, the less he could blab to the Dallas police.