David Letterman’s longtime cue-card holder says he wound up cuing his own firing by getting aggressive with a colleague.

Tony Mendez tells the New York Post in a story published on Sunday that he lost his job after grabbing a co-worker by the shirt on October 9 behind the scenes at CBS’ Late Show with David Letterman.

CBS directed an inquiry to Letterman’s production company, Worldwide Pants. A spokesman said Worldwide Pants won’t comment on personnel matters.

Attempts to reach Mendez weren’t immediately successful on Sunday.

The 69-year-old Mendez tells the Post he knows he shouldn’t have laid a hand on his colleague. He says Letterman wasn’t apprised of any tensions between the two.

Mendez has become familiar to Late Show viewers, appearing in episodes going back to at least 1997.