Art Streiber/CBS

The Navajo Nation is speaking out over a joke that aired on CBS' "Mike & Molly" referring to Native Americans as "drunk Indians."

In the episode that aired last week, Mike's mother Peggy, who is played by Rondi Reed, quipped, "Arizona? Why would I move to Arizona? It's nothing but a furnace full of drunk Indians."

Erny Zah, a spokesperson for the Navajo Nation, which occupies parts of Arizona, told ABCNews.com, "It's offensive, it's derogatory, it's deplorable. Ignorance is one thing, but this must have passed through a lot of eyes before it appeared on a network show."

Zah added, "An apology would be appropriate but it can't fix the damage done."

Both CBS and Warner Bros., which produces "Mike & Molly," declined to comment for this story.

Zah said neither the network nor producers have been in touch with the Navajo Nation.

"Alcoholism is a real issue on our reservations and it's not funny," Zah said.

Mike & Molly stars Melissa McCarthy and Billy Gardell.