Former secretary of state, former Nixon administration official, Lawrence Eagleburger said on Crossfire:
EAGLEBURGER: Probably. You know, President Nixon once suspected him. I'm surprised he didn't end up dead somewhere because of that. But nevertheless, I think he did suspect it. I think, if you think about it now, it is at least very likely.
Does he imply that Nixon would have had him whacked?
Vanity Fair article: Here's the link if you want
to read it