The company said it would take affected boxes from warehouse and store shelves. General Mills noted that wheat flour was "inadvertently introduced" to the gluten-free oat flour system in an "isolated incident."
The recall includes four days of production of original Cheerios and thirteen days of production of Honey Nut Cheerios made in July. Cheerios tweeted how consumers can identify if a box they bought was affected.
General Mills shares closed up about 1 percent higher on Monday.