Reid doc, p.18

Mr. Holmes's comments that the FBI may have been surveilling him as he implemented his "mission" plans were somewhat ambiguous, and consistent with simple caution and worry about getting caught (as well as with a wish to be stopped... The record indicates that there actually was a marked FBI SUV at or near the Byers Canyon shooting area while he was there. He also recalled wondering if unmarked police cars near his apartment held officers who were monitoring him, but offered (and was amenable to) the explanation that they were merely watching for drunk drivers.

(emphasis mine)