While rice is cooking, in Dutch oven, combine tomatoes, carrots and leek; mix well. Bring to a boil. Reduce heat; cover and simmer while preparing meatballs.
In large bowl, combine all remaining ingredients except zucchini; mix thoroughly. Shape mixture into 1-inch balls. Place in simmering sauce; cook 5 minutes.
Add zucchini; simmer an additional 5 to 7 minutes or until meatballs are no longer pink in center. Serve over rice.