A new feud has emerged on The Hills: Audrina Patridge vs. Kristin Cavallari.
"I don't like her," Patridge confessed Thursday on Ryan Seacrest's KIIS-FM radio show.
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She confirmed the two had a fight the first day of filming bonus episodes of the MTV show (it has been rumored that Cavallari has been pursuing Patridge's ex, Justin Bobby).
Patridge was mum on what went down, but told Seacrest, "When someone gets in my face, I have to defend myself. And, you guys, I mean, I can't say much. They'll show it, but I mean, all I have to say is, it's really pathetic and desperate what people will do when the cameras are around."
"It was my birthday, and I was like, Oh, my God. Is this what we're going to have to deal with?'" she added.
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Patridge wouldn't open up about her recent fling with Star Trek hottie Chris Pine.
Us Weekly reported that the two met at ShoWest in Las Vegas in early April. On May 15, she was spotted leaving his L.A. apartment building.
"There's always speculation of anyone I hang out with or anything I do," a coy Patridge told Seacrest.
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Pressed for more, she replied, "My lips are sealed."
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Still, she said, "From Justin Bobby, I think any guy is an upgrade. I mean, I've learned so much since that relationship."