West Valley, Utah (CNN) Mitt Romney on Saturday called some of the disclosures made by former FBI Director James Comey in his explosive new book "unusual" and "disappointing" and said the excerpts he'd seen were not what he'd expect from a former FBI director.

"I did find it unusual and somewhat disappointing to have an FBI director go into such personal reactions — as opposed to 'nothing but the facts, ma'am; only the facts,'" Romney said in an interview with CNN at Utah's GOP convention.

The US Senate candidate, who is vying to replace retiring Sen. Orrin Hatch, said the excerpts of "A Higher Loyalty" that he saw "read a bit too much like a novel."

"I haven't read it, but the excerpts that I've seen, it struck me -- this isn't what I would have expected for a FBI director," he said. "I would have expected this from a former Cabinet member, or a member of the White House staff, but somehow felt that the FBI director was more separate from those kinds of comments."

At the same time, Romney said Comey probably felt the need to respond after his rough treatment by the White House.

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