Editor's note: Please note, this story contains graphic language.
(CNN) -- The CEO of pizza giant Papa John's has apologized to a Sanford, Florida, customer after a delivery man accidentally dialed the customer and left a racist rant on the man's voice mail.
The apology came after a customer posted on YouTube a video of the voice mail message, which featured the delivery man using racial slurs as he complained to another Papa John's employee about the size of tips he receives from African-Americans.
The customer, who is not identified and is not shown on camera, shows the receipt for $15.26 and said he gave the delivery man a $5 tip -- more than 20% -- on Sunday. Then the customer plays the roughly four-minute message.
"I guess that's the only requirement for being a (n-word) in Sanford," the driver told a colleague. "... Yeah, they give me five bucks there -- fine outstanding African-American gentleman of the community."
The driver's colleague can be heard laughing.
During the message, the delivery man can be heard singing the racial slur repeatedly.
The video went viral, generating an outcry on social media. Papa John's CEO John Schnatter took to social media, posting an apology on Facebook and Twitter for "the reprehensible language used by two former employees."
"Their thinking and actions defy both my personal and the company's values and everything for which this company stands. The employees responsible for this absolutely unacceptable behavior were immediately terminated," Schnatter wrote on Monday.
"My heartfelt apology goes out to the customer involved, his family, and our community at large. I am very sorry that anyone would be exposed to these hurtful and painful words by any person involved in any way with our company."
Schnatter said he also personally reached out to the customer to "share my own thoughts and offer my deepest apology."
The incident came as Sanford remains in the national spotlight because of the 2012 shooting death of an unarmed black teenager.
The shooting raised questions about race relations and sparked large protest in Sanford after police declined to arrest George Zimmerman, who said he shot 17-year-old Trayvon Martin in self-defense. Zimmerman goes to trial next month on a charge of second-degree murder in connection with the killing.
CNN's Chelsea J. Carter contributed to this report.