TAMPA, Fla. (WFLA) — Florida deputies seized enough fentanyl that could kill 5 million people after a weeks-long investigation, according to Polk County Sheriff Grady Judd.

The sheriff’s office said three people were arrested for their involvement in a drug trafficking operation that transported fentanyl from the Sinaloa Cartel to Compton, California, before making it to Florida.

“They tried to treat us with fentanyl, and we tricked them with an arrest,” Sheriff Grady Judd said during a Tuesday press conference.

According to the sheriff’s office, the investigation into the drug trafficking began in September as undercover detectives investigated three men living in Hillsborough County, two of whom were said to be Mexican nationals who entered the country illegally.

The three suspects were identified as Juan Manuel Gutierrez Medina, 55; Ruperto Rocha, 65; and Juan Gutierrez Contreras, 25.

Detectives said they conducted controlled purchases from Gutierrez Medina, who sold them large quantities of fentanyl. They also said they made these purchases with the other two suspects as well.

Authorities tracked Gutierrez Medina as he traveled from Compton to Florida. Deputies said the Florida Highway Patrol arrested him in Suwannee County on Oct. 18.

The sheriff’s office also arrested Rocha on Oct. 12 and Gutierrez Contreras on Oct. 25.

Detectives said before Gutierrez Contreras’ arrest, the suspect delivered 6 kilograms of fentanyl to undercover agents. In total, detectives seized 10 kilograms in the investigation.

“Ten kilograms is enough fentanyl to kill 5 million people if taken in overdose amounts,” Judd said. “These drugs are extremely dangerous.”

According to the Centers for Disease Control and Prevention, fentanyl “is a synthetic opioid that is up to 50 times stronger than heroin and 100 times stronger than morphine.” It contributes to many overdoses in the United States, some of which end in death.

Fentanyl comes in two forms, pharmaceutical fentanyl and illegally manufactured fentanyl. While the pharmaceutical product is used to treat severe pain, illegal fentanyl can come in many forms and is often mixed with drugs like heroin, cocaine, and methamphetamine, according to the CDC.