"She felt uncomfortable with [Morrison's] line of comments and went to producers, who then got Fox involved," the source tells PEOPLE

A source close to the Fox reality show tells PEOPLE that Morrison, 43, was fired from the series "after he had an inappropriate relationship with a female contestant."

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"They didn't have sex, but he reached out to her through flirty direct messages on social media," the source says. "She felt uncomfortable with his line of comments and went to producers, who then got Fox involved. He was fired after they did their own investigation."

The source adds that Morrison and the unidentified female contestant "never met up off-set."

"It was just messages that crossed the line," the source notes.

Reps for Morrison and Fox did not immediately respond to PEOPLE's request for comment.

Matthew Morrison Matthew Morrison | Credit: Mike Yarish/FOX

News that the Tony Award-nominated Broadway star had exited SYTYCD broke on Friday, a little more than a week after the dance competition series aired its season 17 premiere on May 18.

At the time, Morrison said in a statement to PEOPLE that he was leaving the show after failing to follow "competition production protocols."

"Having the opportunity to be a judge on So You Think You Can Dance was an incredible honor for me. Therefore, it is my deepest regret to inform you that I will be leaving the show," Morrison said in the statement.

Matthew Morrison Matthew Morrison | Credit: Ian West/PA Images/Getty

"After filming the audition rounds for the show and completing the selection of the 12 finalists, I did not follow competition production protocols, preventing me from being able to judge the competition fairly," he continued. "I cannot apologize enough to all involved and I will be watching alongside you all on what I know will be one of the best seasons yet."

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