Following the news that "The Walking Dead" writer and showrunner Glen Mazzara has left AMC's mega-hit TV series, The Hollywood Reporter is reporting on the behind the scenes drama that led to the shift, though creator Robert Kirkman has publicly stated the criticisms are not based in fact.

Mazzara's former co-worker and now current showrunner for ABC's "Last Resort" Shawn Ryan and FX's "Sons of Anarchy" showrunner Kurt Sutter have spoken out publicly and bluntly with their reactions to the dismissal. "It's a real question now why good showrunners should sell to AMC," Ryan is quoted from Twitter, with Sutter adding that AMC had sent him "a gift basket filled with ... broken promises and the marinated tongue used to lick Kirkman's ass."

THR cites "insiders" who claim Kirkman exerts a high level of control over the series and that he himself had issue with how Mazzara saw "The Walking Dead" moving forward. Another source sides with Kirkman and AMC, stating that Mazarra's weaknesses as showrunner became "abundantly clear ... especially for the second half of the season," claiming production on the show was shut down "several times" due to a lack of material.

Kirkman's only response to date is a tweet declaring "@sutterink is brilliant and Sons is my favorite show on TV. Still, it's upsetting to see him ranting about things he knows nothing about."

When Mazzara's split from the show was initially announced, Kirkman and AMC described the parting as mutual, citing "a difference of opinion about where the show should be going forward."

"I am in full support of both AMC and Glen Mazzara in the decision they have come to and believe the parties came to this decision in the best interest of the future of the show," "Walking Dead" creator Robert Kirkman said in a statement. "I thank Glen for his hard work and appreciate his many contributions to 'The Walking Dead' and look forward to working with him as we complete post production on Season 3."

"My time as showrunner on 'The Walking Dead' has been an amazing experience, but after I finish season 3, it's time to move on," Mazzara said in a statement issued with the initial announcement of his leaving the series. "I have told the stories I wanted to tell and connected with our fans on a level that I never imagined. It doesn't get much better than that. Thank you to everyone who has been a part of this journey."