Michigan's WK Kellogg Co., the cereal giant, is set to be acquired by the Italian candymaker behind Ferrero Rocher in a nearly $3 billion deal, the Wall Street Journal reported Wednesday. A deal with parent Ferrero SpA, the maker of Butterfinger candy bars and Nutella hazelnut spread, could be finalized as soon as this week, according to reports.

Shares in Kellogg, the Battle Creek-based maker of Frosted Flakes, Cheerios, Froot Loops and other breakfast cereals, closed Wednesday at $17.50, but skyrocketed more than 50% in after-hours trading on news of a prospective deal. Phone and email requests by The Detroit News to Ferrero in Italy and Kellogg in Battle Creek were not immediately returned Wednesday.