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What's the big idea? Joan Rivers was not a happy camper (and rightfully so!) when the comedienne had cake thrown at her at the QVC Red Carpet Style event in L.A. on Friday. But what first seemed like a scary incident, turned out to be a silly prank the E! Fashion Host concocted with Miss Piggy.

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"Someone threw cake at Joan Rivers as she was leaving the QVC event at the Four Seasons. It was nuts," an eyewitness told Us of the joke. "She was leaving the event and someone chucked the cake and she screamed."

"She was absolutely covered. She was yelling for her car," added the insider. "It was outside of the event. Joan was frantic and trying to get through the crowd."

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Indeed, Rivers, 80, looked absolutely miserable, but it was all in fun! Shortly before getting covered in frosting from head-to-toe, the comedienne was caught arguing with the Muppet. "You're not going anywhere -- did you touch my breast?" she was overheard yelling. Miss Piggy replied: "Next time I'll kick you in the chin!"

As previously reported, Miss Piggy will be going head-to-head with Rivers with her own lifestyle brand on QVC. Her "Miss Piggy Haute Tote" appearance will air on March 16.

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"As a world class diva, it's not just a good idea to have your own lifestyle brand -- it's the law," the Muppet told Us exclusively on Feb 28. "Many people don't realize it, but if you don't turn yourself into an empire, you can lose your diva's license."

"I will be the greatest thing to come to QVC, and I look forward to being the reigning queen of shopping," she added. "If Joan Rivers can do it, I can do it better."


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