Based on Leonard's Pronto, Riding the Rap and his short story "Fire in the Hole," FX's Justified follows Deputy U.S. Marshal Raylan Givens ( Timothy Olyphant ) as an old-school lawman who is reassigned from Miami to rural Eastern Kentucky. The TV series debuted in 2010, with its fifth season scheduled to premiere in January 2014.

UPDATED: FX Networks CEO John Landgraf confirmed the decision was based on a discussion he had with Graham Yost and star Timothy Olyphant.

It's official: The sixth season of FX's Justified will be its last.

The Western starring Timothy Olyphant will conclude its run with season six, FX Networks CEO John Landgraf told reporters Tuesday at the Television Critics Association's winter press tour.

"It was [showrunner] Graham Yost and Timothy Olyphant's decision," he said. "I would have liked to have had more Justified. It's one of my favorite shows."

Landgraf noted that he reluctantly accepted the decision from the duo to wrap up the series. "We talked about it a year ago. They felt that the arc of the show and what they had to say would be best served by six seasons instead of seven," he said. "Regretfully, I accepted their decision."

The executive stressed that network has never let business drive the creative and has never extended a show -- or ended a show -- based on financials.

"A lot of it was just figuring out how much story we had left," Yost said, later in the afternoon. "Our biggest concern is running out of story and repeating ourselves. This was a long conversation. There were financial incentives to keep going, but it really felt, in terms of story, that six years felt about right."

The move to wrap Justified comes as FX has been bulking up on originals following the launch of younger-skewing sibling network FXX, which has thus far been a home for comedy. FX this year will launch anthology series Fargo as well as Guillermo del Toro and Carlton Cuse's The Strain and Howard Gordon's Tyrant. They join a drama lineup that includes returning series American Horror Story, The Bridge, The Americans and the final season of its top-rated show, Sons of Anarchy.

Additionally, FX took TCA to announce that the cast and crew would be participating in a tribute to late writer Elmore Leonard (author of source material Fire in the Hole) at Santa Monica's New Roads School on Jan. 21.

Every episode, we've tried to do as a tribute to Elmore Leonard," added Yost.

Editor's note: This story has been updated to reflect that Justified would end after season five.

E-mail: Lesley.Goldberg@THR.com

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