"If I had to guess 25 cents, this would be exactly that. Homegrown, or maybe a mentally deranged person, or somebody with a political agenda that doesn't like the health care bill or something. It could be anything," he said.
"There is no evidence here of a conspiracy, there is no evidence that it's tied into anything else. It looks like an amateurish job done by at least one person," he told Couric."