To rub salt into the wound, McDonald's Japan admitted Wednesday that a human tooth was mixed unintentionally into an order of french fries last summer.

The latest incident hitting the fast-food giant came a day after the company revealed two incidents involving foreign objects found in servings of chicken nuggets.

At a news conference, McDonald's Holdings Co. (Japan) executive Takehiko Aoki and McDonald's Co. (Japan) executive Hidehito Hishinuma admitted the company headquarters received a complaint from a customer last August who found the tooth in her order of french fries at an Osaka outlet.