See’s Candies says some heart-shaped boxes of chocolates shipped for Valentine’s Day have been mislabeled and may contain nuts.

The San Francisco-based company is warning people with allergies to coconut, almonds, walnuts or pecans to avoid eight-ounce boxes labeled “Classic Red Hearts with Assorted Chocolates.”

The candies were shipped nationwide.

No illnesses have been reported.

See’s, which has factories in San Francisco and Los Angeles, says the packages can be returned for refunds.

City News Service reported Saturday that the allergy alert was issued when it was noticed that at least one incorrectly labeled box was mixed in with properly labeled boxes.