Several packages of the powdered drug were found during a traffic stop on Interstate 5.
"If you look at that total amount, that was enough to kill seven and a half million people," said Sheriff Zanoni.
This year alone in Fresno County, 48 deaths have been fentanyl-related.
32-year-old Mario Hernandez and 21-year-old Manuel Lopez are both from Sinaola, Mexico.
They were arraigned yesterday on charges of possession of narcotics for sale -- and can face up to 15 years if convicted.
Two weeks before Hernandez and Lopez arrests, detectives arrested Jose Araujo-Valenzuela along I-5, also from Sinaloa.
Araujo-Valenzuela had 240,000 Fentanyl laced pills. He could be incarcerated for over 11 years if found guilty.
Araujo-Valenzuela has no bail. Manuel's bail is set at $35,000, while Mario's bail is set at $45,000.
Sheriff Zanoni says the cartels are moving narcotics along the highway like any other cargo.
"It's dangerous, and until you've lost a loved one or you've seen the effects -- or talked to somebody who is a fentanyl addict, you don't realize how powerful this is and how bad it is," said Sheriff Zanoni.
20-year-old Frankie DePrima was just one of those people.
"Somebody gave him a Xanax laced with fentanyl; those were pressed pills made by a drug dealer," said Elaine Hudson, who lost her son to fentanyl.
Elaine Hudson deals with the pain of losing her son every day and wants to see traffickers stay behind bars.
"I wish that these drug dealers could get harsher penalties because I feel like its not enough time for them," said Hudson.
Now she wears her Frankie bracelet every day, as a reminder of her son -- whose life was cut short because of dangerous drugs.
"It's hard, it's hard not having Frankie here; I miss him every single day," said Hudson.
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