LOS ANGELES – He called two black hecklers the “n-word” and enthusiastically referenced a time when blacks were often victims of civil rights abuses, but Michael Richards said his verbal barrage during a stand-up routine was fueled by anger and not bigotry.

“For me to be at a comedy club and flip out and say this crap, I’m deeply, deeply sorry,” the former “Seinfeld” co-star said during a satellite appearance for David Letterman’s “Late Show” in New York.

“I’m not a racist. That’s what’s so insane about this,” Richards said, his tone becoming angry and frustrated as he defended himself.

Richards described himself as going into “a rage” over the two audience members who interrupted his act Friday at the Laugh Factory in West Hollywood.

His explanation was reminiscent of Mel Gibson’s assertion that he wasn’t anti-Semitic after he let off a barrage of Jewish slurs during a traffic stop last summer: despite what came out of his mouth, that’s not what is inside him.

Industry colleagues were in no hurry to accept Richards’ apology.

“Once the word comes out of your mouth and you don’t happen to be African-American, then you have a whole lot of explaining,” comedian Paul Rodriguez, who was at the Laugh Factory during Richards’ performance, told CNN. “Freedom of speech has its limitations, and I think Michael Richards found those limitations.”

His Laugh Factory tirade began after the two clubgoers shouted at him that he wasn’t funny. A videotape of the incident was posted on TMZ.com.