Police in Independence, Missouri have recovered five Barbie doll packages that contained fentanyl after being alerted by store security about suspicious substances.

Authorities said store security at Cargo Largo, a local discount store, contacted police regarding a suspicious powder substance found in the packaging of Barbie dolls. Upon investigation, police confirmed the presence of fentanyl in the packages.

According to police statements released Saturday, all five packages containing the dangerous substance have been recovered. The dolls had been sold at the discount store before the discovery was made.

Fentanyl is a synthetic opioid that is significantly more potent than heroin and has been linked to a surge in overdose deaths across the United States. The drug is often mixed with other substances and can be lethal in very small amounts.

The investigation into how the fentanyl came to be in the toy packaging is ongoing. Police have not released additional details about the circumstances surrounding the contamination or whether any arrests have been made in connection with the incident.