A tomato recall due to risk of salmonella contamination has been designated as Class I, the U.S. Food and Drug Administration's highest warning level, the agency said. The FDA marked the tomato recall affecting three states as Class I, meaning there is a risk of "serious adverse health consequences or death," on May 28.

Williams Farms Repack issued a recall for the tomatoes, the FDA announced last month. It's now labeled deadly.

The recall of tomatoes distributed in three southern states was upgraded to the most severe warning the agency issues.