TAMPA, Fla. (WFLA) — Two men suspected of buying and selling “large quantities” of fentanyl were arrested after authorities in Clay County uncovered enough of the lethal drug to kill more than 4 million people.

An investigation began in July 2022 when the Clay County Sheriff’s Office, along with Attorney General Moody’s Office of Statewide Prosecution, discovered shipments of blue and purple fentanyl bricks coming from California.

According to the investigation, Alvin “AJ” Mercado and Jason Setzer sent U.S. currency to the supplier in return.

Authorities said Mercado coordinated drug orders and shipments, and brought packages to Setzer’s home where Setzer broke them into smaller quantities and distributed them to other dealers in the area, including Duval County.

During a Wednesday news conference, Moody announced that 8.35 kilograms of fentanyl, 1.36 kilograms of cocaine, 2.38 kilograms of methamphetamine, and other drug trafficking paraphernalia had been seized. A lethal dose of fentanyl is just two milligrams.

Authorities said there was enough fentanyl to kill more than 4.18 million people — roughly the populations of Alachua, Baker, Bradford, Clay, Columbia, Duval, Flagler, Gilchrist, Hamilton, Lake, Levy, Marion, Nassau, Putnam, Seminole, St. Johns, Union and Volusia counties combined.

“These drug traffickers compiled enough of this deadly synthetic opioid to kill everyone within 18 counties of their criminal operation,” Moody said. “Thankfully, working with the Clay County Sheriff’s Office, we were able to take these deadly drugs off the streets before they could kill Floridians.”

Setzer was charged with trafficking in fentanyl, trafficking in cocaine, trafficking in methamphetamine, possession of more than 20 grams of cannabis, conspiracy to traffic in fentanyl in excess of 2,000 grams and possession of a firearm by a convicted felon. If convicted, Setzer faces up to 140 years in prison. He was held in the Clay County Jail on a total bond of $17.1 million.

Mercado was charged with trafficking in fentanyl and conspiracy to traffic in fentanyl in excess of 2,000 grams. If convicted, he faces up to 60 years in prison. He was held on a $10 million bond.

“If you are dealing drugs or involved in the drug trade in any way, shape, or form in Clay County, WE are coming for you,” Clay County Sheriff Michelle Cook said. “I PROMISE you, every member of the Clay County Sheriff’s Office will continue working hard every day to keep drugs off of Clay County streets.”