Thomas Gibson has been dismissed from long-running CBS drama Criminal Minds.
ABC Studios and CBS Television Studios, which produce the series, made the announcement on Friday, providing no further details.
Gibson's exit followed a physical altercation last month between him and another member of the Criminal Minds company on the series' Los Angeles set.
It occurred as the series filmed an episode for the upcoming season, its twelfth, according to a person with knowledge of the incident who spoke on condition of anonymity because they weren't authorised to discuss it.
The altercation reportedly led to an internal review.
The firing was preceded by an apology from Gibson on Thursday.
"There were creative differences on the set and a disagreement. I regret that it occurred," Gibson said in a statement.
Gibson had starred on Criminal Minds - which focuses on an elite team of FBI profilers who try to anticipate and prevent criminal behaviour - since its premiere in 2005. He played Special Agent Aaron Hotchner. He had also directed six episodes in recent years.
Details on how Hotchner will be written out of the show "will be announced at a later date", the studios said.
Remaining stars of the ensemble series include Joe Mantegna, Matthew Gray Gubler, A.J. Cook, Kirsten Vangsness, Aisha Tyler and a newcomer this season, Adam Rodriguez.
"I love 'Criminal Minds' and have put my heart and soul into it for the last 12 years," Gibson said in a statement on Friday.
"I had hoped to see it through to the end but that won't be possible now. I would just like to say thank you to the writers, producers, actors, our amazing crew, and, most importantly, the best fans that a show could ever hope to have."
The 54-year-old Gibson had previously starred in the sitcom Dharma & Greg and the hospital drama series Chicago Hope.
The new Criminal Minds season begins on September 28.
