A major shake-up for the “Heroes” production staff took place this weekend, as writers/co-executive producers Jesse Alexander and Jeph Loeb have been let go from the program, this according to a report Sunday evening from Variety.

Both writers/producers have been with the show since its inception and have been instrumental in the production, running day-to-day operations under the guidance of series creator Tim Kring.

The change comes at a critical moment for the program, which has struggled in the ratings in its third season, down from Season Two, amid complaints from fans and critics about the direction of the program. According to Variety, the duo were “let go because of [NBC] execs' frustration with the creative direction of the show.”

Sunday evening, CBR News spoke exclusively with Loeb who said, “As of today, Jesse Alexander and I have left ‘Heroes.’ I'm incredibly proud to have been a big part of the success a show with eight Emmy nods and a win this year for NBC.com. I will miss the superb cast and writing staff and wish everyone the best.”

Loeb has completed writing/producing the fall finale, the last episode of the “Villains” chapter titled “War.”

Alexander commented on the dismissal Sunday evening on his blog. "I write this with a heavy heart. As of today I am no longer a writer/producer on 'Heroes.' I could not be prouder of all the work I did on the show and wish all my Heroic Scribbler pals the very best."

More on this story as it develops.