The co-creator and executive producer of CW/Warner Bros’ DC franchise, which includes The Flash, Supergirl, Legends of Tomorrow, and Arrow, is in hot water over multiple allegations of sexual harassment.

Kreisberg is a top producer at the CW/DC franchise, serving under Greg Berlanti. He has his hands in all the DC Comics shows on the network, with a primary focus on The Flash.

Over the weekend, Warner Bros. TV Group announced that it has suspended the showrunner from his duties at the studio as it investigates the accusations.

Multiple staffers on The Flash lodged complaints with WBTV about Kreisberg’s behavior. According to the allegations, Kreisberg interacted with a young female writer on The Flash early in the show’s run in what someone close to the situation referred to as “inappropriate” and creating “a hostile work environment,” according to Deadline.

The woman had worked under Kreisberg in various capacities and those familiar with the situation says that his behavior only got worse over time. Eventually, she met with Kreisberg on a Friday and informed him that she wanted to be released from her contract early and leave The Flash.

According to Deadline, Kreisberg asked her to wait and talk to other staffers who encouraged her to stay until the end of the season because there were only two weeks left. Sources say that she declined to stay and left after a few days because working with Kreisberg made her uneasy.

The writer did not cite sexual harassment for her reason for leaving, but the “toxic” environment on the WBTV series caused by Kreisberg.

In addition to the woman, Deadline reports that there are specific allegations from another woman—a director who helmed episodes of Arrow and The Flash, who complained of similar behavior from him.

“We have recently been made aware of allegations of misconduct against Andrew Kreisberg,” WBTV said in a statement Friday night. “We have suspended Mr. Kreisberg and are conducting an internal investigation. We take all allegations of misconduct extremely seriously, and are committed to creating a safe working environment for our employees and everyone involved in our productions.”

“There is nothing more important to us than the safety and well-being of our cast, crew, writers, producers and any staff,” added WBTV. “We do not tolerate harassment and are committed to doing everything we can to make an environment that’s safe to work in and safe to speak up about if it isn’t.”