Bob Novak, unhappy at being interrupted by James Carville, who then made fun of Novak, said to Carville on the air, "This is bullsh*t" and walked off the set. Crooks and Liars has the video.

The segment began with Novak joking about the Katherine Harris make-up flap. Novak proceeds to political analysis of Harris's chances in the Senate race. Carville interrupts him, and he asks to finish. Carville responds:

Carville: "You've gotta show these right-wingers some kind of backbone, you know, the Wall Street Journal editorial page is watching you show them you're tough."

Novak says "that's bullsh*t. Then he says "Let it go." But, the segment host, Dan Harris Ed Henry, threw the next question to Carville instead of letting Novak finish his answer. So Novak walked off the set.

Media Bistro reports a CNN spokesperson later said:

"Bob Novak's behavior on CNN today was inexcusable and unacceptable. Mr. Novak has apologized to CNN, and CNN apologizes to its viewers for his language and actions. We've asked Mr. Novak to take some time off," a CNN spokeswoman told us.

The AP now has the story.