Big Brother host Julie Chen had more to say about the racist comments made by a houseguest in a recent interview with David Letterman.

Chen appeared on The Late Show with David Letterman Tuesday night to discuss the racist comments made by evicted houseguest Aaryn Gries.

"She's 22. She's college-educated. It was shocking and it was astounding to watch because when she first got picked to be one of the housemates, we all thought, 'Oh, she's going to be America's sweetheart.' She's a beautiful girl," Chen admitted. "But you have to remember, it's people trying to get picked. It's kind of like a job interview - they're putting their best foot forward. And it wasn't until a couple weeks in the house that she said some pretty ugly things."

Chen grilled Gries when she was evicted by her fellow houseguests on Thursday night's live Big Brother show. Some of the comments Gries made included not being able to see a black contestant in the dark and telling an Asian contestant to "go make some rice."

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"They all know everything they say and do is being broadcast live to the Internet and intentionally getting on the network broadcast," Chen explained. "To say such ugly things, that's heartbreaking."

Chen also admitted that it was difficult for her to interview Gries on Thursday, considering all of her comments.

"I had to just put on my journalist hat and play it straight down the middle and read it back, verbatim, her words. ... She did apologize. She seemed dumbfounded by her own words. I do applaud the fact that she said 'I'm sorry if I offended anyone.' But then she talked out of the other side of her mouth and she said, 'But.' Any time you apologize and there's a 'but,' to me, it's not a real apology."

Gries' mother, Elizabeth Owens, released a statement on Tuesday saying she was "disappointed" with the way Chen conducted Thursday's interview, saying that she "attacked" her daughter. Gries was fired from her modeling agency earlier this summer after her racist comments were capture on the Big Brother live Internet feeds. Fellow houseguest GinaMarie Zimmerman was fired from her pageant coordinator job for making similar racist comments.

As the racist comments were a defining moment of the current Big Brother season, they will likely be addressed on the Sept. 18 finale and reunion show.

The next episode of Big Brother 15 airs Wednesday at 8 p.m. on CBS.

To watch Chen's comments on Letterman, click here. (Skip to 35:00 for Chen's comments)

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