E! has suspended The Royals creator Mark Schwahn following accusations of sexual harassment by actresses on his former The CW series, One Tree Hill.

Credit: Monica Schipper/FilmMagic

Another TV showrunner has been suspended after allegations of sexual misconduct.

E! has suspended The Royals creator Mark Schwahn following accusations of sexual harassment by actresses on his former The CW series, One Tree Hill.

“E!, Universal Cable Productions and Lionsgate Television take sexual harassment allegations very seriously, investigate them thoroughly and independently, and take appropriate action,” reads a statement from the network and studios. “Lionsgate has suspended Mark Schwahn from The Royals as we continue our investigation.”

Reps for Schwahn have not yet replied to EW’s request for comment on the allegations.

Filming recently wrapped on season 4 of The Royals in September and will air as planned next year on E!

Schwahn was accused of sexual harassment and physical and emotional manipulation by 18 female cast and crew members who worked on the TV drama — including stars Sophia Bush and Hilarie Burton — which aired from 2003 to 2012 on The WB and The CW.

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A joint letter, which was first reported by Variety, asserts that “Schwahn’s behavior over the duration of the filming of One Tree Hill was something of an ‘open secret.’ Many of us were, to varying degrees, manipulated psychologically and emotionally. More than one of us is still in treatment for post-traumatic stress. Many of us were put in uncomfortable positions and had to swiftly learn to fight back, sometimes physically, because it was made clear to us that the supervisors in the room were not the protectors they were supposed to be. Many of us were spoken to in ways that ran the spectrum from deeply upsetting, to traumatizing, to downright illegal. And a few of us were put in positions where we felt physically unsafe. More than one woman on our show had her career trajectory threatened.”

E!’s move comes on the heels of The CW suspending Andrew Kreisberg, an executive producer on DC series The Flash, Supergirl, Legends of Tomorrow, and Arrow, after 19 staffers accused him of inappropriate conduct. Kreisberg has strongly denied the allegations to Variety.

This article originally appeared on Ew.com