The Italian candy maker behind Ferrero Rocher and Nutella is nearing a roughly $3 billion deal to buy the breakfast-cereal conglomerate WK Kellogg, according to people familiar with the matter. Ferrero,

Shares of WK Kellogg, the cereal maker behind Froot Loops and Frosted Flakes, skyrocketed as high as 50% after the Wall Street Journal reported Wednesday that Ferrero was nearing acquiring the company for $3 billion.

Ferrero, the European confectionery giant behind Nutella and Ferrero Rocher, is set to acquire WK Kellogg Co ., the maker of Froot Loops and other classic American cereals, in a $3.1 billion deal, according to a press release issued Thursday.