WATCH: K9 alerts deputies to $1 million in fentanyl in car of fugitive wanted in Mexico

JEFFERSON COUNTY, Colo. (KRDO) – A routine traffic stop on I-70 late Sunday night led to the seizure of nearly $1 million worth of fentanyl – and the arrest of an undocumented immigrant wanted in Mexico for sexual assault.

According to the Jefferson County Sheriff's Office (JCSO), at around 10:25 p.m. on April 28, deputies pulled over a black Ford Explorer near I-70 and Harlan Street. After stopping the driver, deputies began to suspect there were narcotics in the car and called in the K9 team to investigate.

When K9 Anton arrived on scene, he quickly confirmed the deputies' suspicions, alerting them to the presence of narcotics near the SUV's rear hatch.

Watch K9 Anton in action:

In the car, deputies discovered 4.9 kilograms of fentanyl, which equates to approximately 50,000 pills with a street value of nearly $1 million, the sheriff's office said.

According to the FBI Denver, the driver of the car was identified as Dario Perez Quintero, who was wanted in Mexico for sexual assault. The agency said Quintero was residing in Colorado "without authorization," and that multiple departments were working to apprehend him when Jefferson County deputies pulled him over.

Quintero has since been turned over to federal agents, the Jefferson County Sheriff's Office said.

"FBI Denver will continue to work with our federal and local partners to target violent criminals and disrupt drug distribution networks in our community," the agency wrote in a post to Facebook about the arrest.

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