Preliminary tests showed that ByHeart baby formula contained the type of bacteria that produces the toxin linked to a botulism outbreak, California health officials said late Saturday.

The outbreak has sickened at least 13 infants in 10 states. No deaths have been reported.

"Consumers in possession of this product should stop using it immediately," the California Department of Public Health said in a statement.

More tests of ByHeart Whole Nutrition Infant Formula are pending as state and federal health officials investigate the outbreak that started in mid-August. The New York-based company this weekend recalled two lots of the powdered product.

Infant botulism outbreak

The outbreak of infant botulism has sickened babies aged 2 weeks to 5 months since mid-August. All were hospitalized after consuming ByHeart powdered formula, according to the U.S. Centers for Disease Control and Prevention.