Prominent television producer, Ryan Murphy, has threatened to sue Warren Leight, a strike captain and member of the Writers Guild of America’s (WGA) Strike Rules Compliance Committee, according to a report by The Hollywood Reporter. This threat has led to Leight stepping down from his positions within the WGA.

The conflict began on June 21 when Leight posted a tweet alleging that crew members on Murphy’s show, American Horror Story, had informed him they would be blacklisted if they crossed the WGA’s picket lines. Murphy’s spokesperson swiftly denied these allegations, labeling them as “absolute nonsense” and “categorically false.”

Following the receipt of a letter from Murphy’s attorney, Leight deleted the contentious tweet and issued an apology and retraction. In his statement, Leight referred to his initial tweet as “unsubstantiated” and “completely false and inaccurate.”

In response to the threatened litigation, the WGA East officers sent a memo to its strike captains, revealing that Leight had stepped back from his duties as co-chair of the Strike Rules Compliance Committee and as a captain.

The Hollywood Reporter revealed that the WGA said in its memo that we will “continue to picket [Murphy’s] shows,” and that the Strike Rules Compliance Committee will investigate all leads concerning potential violations.

(If Murphy is found in violation of the strike rules, he can be suspended or expelled from membership, hit with monetary fines, or censured. After the 2007-08 writer’s strike, the WGA brought members alleged to have violated strike rules before a trial committee, as in the case with Jay Leno, who was cleared of wrongdoing).

The internal squabbling comes as news leaked on June 20 that Murphy, one of the industry’s most powerful showrunners, has been negotiating with Disney to return to the studio with a rich overall deal after his $300 million Netflix pact expired. In the memo to captains, the WGA officers implored them to stay focused on the fight at hand, noting, “Our foe in this fight is not other members, it is the AMPTP. If we turn on each other, the AMPTP wins.”