TNT and Snowpiercer showrunner Josh Friedman are parting ways, Deadline has confirmed.

Friedman was an executive producer and wrote the pilot for Snowpiercer, which was ordered to series by TNT this month. Creative differences are blamed as the reason for the split, sources say. There is no replacement as of yet.

Based on the acclaimed 2013 movie by Bong Joon-ho, Snowpiercer is set seven years after the world has become a frozen wasteland. It centers on the remnants of humanity, who inhabit a gigantic, perpetually moving train that circles the globe. Class warfare, social injustice and the politics of survival are questioned in the television adaptation. Jennifer Connelly and Daveed Diggs star. Doctor Strange helmer Scott Derrickson directed the pilot. The cast also includes Mickey Sumner, Susan Park, Benjamin Haigh, Sasha Frolova, Katie McGuinness, Alison Wright, Annalise Basso, Sam Otto, Roberto Urbina, Sheila Vand and Lena Hall.

The series hails from Marty Adelstein’s Tomorrow Studios and Turner’s Studio T.

Variety was first to report Friedman’s exit.