The spokesman for a national law enforcement association criticized Glenn Beck for comments that a California man says helped inform his plans for a killing spree that resulted in injuries to several highway patrolmen.

Rich Roberts is public information officer for the International Union of Police Associations, which represents about 500 local police unions.

Noting it was his personal opinion, he said Beck “stirs people up and not in a good way. He is a source of problems. I have to watch Beck because I don't have a choice, I have to stay in touch with what is going on.”

Roberts, whose group is based in Sarasota, Fla., made the comments following Media Matters' interview with alleged gunman Byron Williams, who was arrested July 19 in Oakland, Calif., after an incident in which several members of the California Highway Patrol were wounded.

Williams told investigators that he was heading to San Francisco to kill members of the Tides Foundation and the ACLU.

In a recent interview with Media Matters, Williams repeatedly cited Beck when discussing his conspiracy theories that informed his assassination plot.

Beck, Williams said, is “like a schoolteacher on TV.” Williams added, "... he's been breaking open some of the most hideous corruption."

Williams also said: “Beck would never say anything about a conspiracy, would never advocate violence. He'll never do anything ... of this nature. But he'll give you every ounce of evidence that you could possibly need.”

Roberts said Beck's rhetoric is a dangerous thing because it can drive people to violence.

“The Becks of the world are people who are venting their opinions and it is inflammatory, it generates a lot of emotion and generates in some people overreaction that apparently happened in the California case,” Roberts said. “Inflammatory speech has a tendency to trigger those kinds of emotions.”

Roberts added about Beck: “He is self-serving and has no interest in improving, informing or educating.”