A limited number of 13-ounce bags of Tostitos yellow corn tortilla chips were recalled by Frito-Lay in late March because of undeclared milk.

The recall has now been upgraded to Class I, meaning “there is a reasonable probability” that eating the chips could “cause serious adverse health consequences or death”

Some Tostitos Cantina Traditional Yellow Corn Tortilla Chips may contain undeclared milk allergens, Frito-Lay said.