The Real Housewives of New York's producers are now attempting "to mediate the situation so the cast all stays filming," according to the source.
Singer was reportedly filming footage in her New York City apartment with fellow The Real Housewives stars Sonja Morgan and Alex McCord when the incident occurred.
"No one is really sure what exactly spurred her craziness," a second source told Us. "But she got herself worked up over filming this scene and one thing led to another, and she punched the producer. Literally."
"They were supposed to be filming all day at Ramona's apartment, but obviously that ended after the fight."
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