Kraft Foods is recalling millions of boxes of original flavor Kraft Macaroni & Cheese because some of the boxes might contain small pieces of metal.

The Illinois-based food giant announced the recall Tuesday. It affects 242,000 cases – which translates into 6.5 million boxes – of macaroni and cheese in the 7.25-ounce size.

According to the company, the boxes in question have "best when used by" dates ranging from Sept. 18, 2015 through Oct. 11, 2015 and are marked with the code "C2."

They were sold individually and in packs of three, four and five. The company says no other varieties, pasta shapes or package sizes are affected by the recall.

The boxed dinners were sold throughout the U.S., Puerto Rico, and in some countries in the Caribbean and South America. They were not sold in Canada.

Kraft said it has heard from eight consumers so far who say they've found metal in the mac and cheese boxes, but no injuries were reported.

"We deeply regret this situation and apologize to any consumers we have disappointed," the company said in its statement.

The company says consumers shouldn't eat the macaroni and should return it to the store where it was purchased for a full refund.

A complete list of affected products and their coding is posted on Kraft's website.

Consumers also can contact Kraft Foods Consumer Relations at 1-800-816-9432 between 9 a.m. and 6 p.m. Eastern time.