TV production rule #1: Don’t kick the writer.

Thomas Gibson, star of the CBS series Criminal Minds, broke that rule in an on-set incident, reportedly with one of the show’s co-executive producers. After an investigation into the scuffle, ABC Studios and CBS Studios, who jointly produce the series, have announced that Gibson has been dismissed and will not be back for the show’s 12th season. Previously, Gibson had been given a two-episode suspension, but that’s now been changed to his permanent removal from the show. The statement:

Thomas Gibson has been dismissed from Criminal Minds. Creative details for how the character’s exit will be addressed in the show will be announced at a later date.

Gibson has been with Criminal Minds, playing Special Agent Aaron Hotchner, since the show’s premiere back in 2005. According to Deadline, this is actually the second such incident Gibson had on set; several years ago he “allegedly pushed” an assistant director following an argument, and was ordered to attend anger management classes. (It may be time for a refresher course.)

After the most recent incident, Gibson said in a statement that there were “creative differences on the set and a disagreement” and the he felt “regret” about what happened. Prior to his work on Criminal Minds, he was the star of the sitcom Dharma & Greg and the medical drama series Chicago Hope.

Criminal Minds has had several personnel changes through the years (original star Mandy Patinkin left, for example, following season 3) but never quite like this. The show also recently lost longtime star Shemar Moore, leaving an even larger hole for the show to fill in its 12th year, even as it adds Adam Rodriguez and Aisha Tyler to its full-time cast. Criminal Minds returns on September 28, minus one Thomas Gibson. And again, don’t kick people, in or out of television production.