Former "Seinfeld" star Michael Richards says he is sorry for his racial epithet-laden diatribe at a Los Angeles comedy club and insists he is not a racist.
"I got heckled and took it badly and went into a rage," he said in an interview Monday night via satellite on CBS' "Late Show With David Letterman."
The interview was arranged by his former co-star Jerry Seinfeld who had already been scheduled to appear on the program.
Appearing distraught and on the verge of tears at times, Richards said, "I am not a racist! That's what's so insane about this. For me to be on stage, and flip out and say this stuff, I'm deeply, deeply sorry."
Richards' public apology came after video of the rant was posted on the Web site TMZ.com on Monday.
Richards was performing at The Laugh Factory, a popular comedy club in Los Angeles, when a group of boisterous latecomers in the balcony began heckling him.
Some members of the group were African-American, and Richards was seen on the tape shouting, "Shut up! Fifty years ago we'd have you upside down with a [expletive] fork up your [expletive]!"
When audience members gasped, he said, "That's what happens when you interrupt a white man, don't you know?"
The tirade lasted for more than three minutes, with Richards repeatedly using the N-word.
On the video, audience members can be heard shouting back at Richards, "That's uncalled for!"
Comedian Paul Rodriguez, who was at the club and watched as tensions mounted, told ABC News, "I've never seen that before. I believe if he had stayed on stage a minute more we'd have had a, well, we'd have had a riot."
What set the three-time Emmy winner off? A comment yelled by Kyle Doss, who had just entered the club with friends a few minutes before.
"I had said my friend doesn't think you're funny," Doss said. "He could have responded back in a professional way and said something funny, but he responded in a hateful, mean way."
The Laugh Factory invited Richards back the next night, saying he had promised to apologize on stage.
However, he did not, and on Monday, the club owner -- facing outrage from civil rights groups -- banned Richards from performing there.
"He's not welcome to this club," Jaime Masada said at a news conference to the applause of a handful of community activists in attendance.
On "The Late Show," Richards said he had some "personal work to do."
His image as the lovably off-kilter Kramer may be forever altered.