General Mills has sued Chobani over an advertising campaign, saying its rival firm is wrongly comparing its yogurt to bug spray.

The suit, filed Sunday in U.S. District Court in Minneapolis, alleges false advertising in a campaign for Chobani Simply 100, a Greek-style yogurt with 100 calories.

Chobani pioneered and then mastered the Greek yogurt business over the past seven years, taking market share from established yogurt kings Dannon and Yoplait, which is owned by General Mills. Dannon and General Mills have fought back, and Yoplait Greek 100 has been the brand's biggest success in Greek yogurt.

Chobani's ads claim that Yoplait Greek 100 contains a pesticide "to kill bugs," General Mills said in its complaint. "In fact, the television commercial that leads the Chobani Attack Campaign goes so far to convey that, because Yoplait Greek 100 is laced with a pesticide, it is so dangerous and unfit to eat that consumers should discard it as garbage."

Chobani falsely claims that Yoplait is "toxic" because it contains the ingredient potassium sorbate, a preservative that is "considered by multiple federal agencies to be a safe and non-harmful food ingredient," General Mills said in the suit.

Last week, Dannon, another yogurt heavyweight, threatened to sue Chobani over the same ad campaign, which criticized Dannon's Light & Fit because it contains sucralose, an artificial sweetener processed with "added chlorine." Light & Fit was also portrayed by Chobani, which is based in upstate New York, as a product that's better off in the garbage.

Before Dannon could make good on its lawsuit threat, Chobani sued Dannon on Friday in federal court in New York asking for a declaration that its claims for Simply 100 do not constitute false and deceptive advertising. Dannon has since filed a counterclaim against Chobani, saying among other things that chlorine isn't added to sucralose.

Chobani on Monday criticized both General Mills and Dannon.

"While I'm not surprised, I'm disappointed that Dannon and General Mills are focused on stopping people from having the facts about artificial sweeteners and artificial preservatives," Peter McGuinness, Chobani's chief marketing and brand officer, said in a statement. "This campaign is about giving people truthful and accurate information so they can make more informed decisions about the food they buy."

The kerfuffle comes at a time when consumers are increasingly scrutinizing packaged food labels for artificial ingredients.

Potassium sorbate is regarded as a safe food ingredient by the U.S. Food and Drug Administration. Chobani's website links to a document from the U.S. Environmental Protection Agency that lists ingredients that can be used in "minimum risk pesticide products." It includes potassium sorbate, as well as cinnamon, cloves, garlic and peppermint oil.

General Mills rejected the notion that the preservative is a bug killer. "General Mills is informed and believes that there is no scientific evidence that potassium sorbate is effective against insects," the company said in the suit.

General Mills is seeking a preliminary and permanent injunction to stop the ads and is asking for damages.

Mike Hughlett • 612-673-7003