A yearlong investigation into large shipments of heroin being delivered to Sonoma County from the South Bay resulted this week in three arrests and the seizure of about 6 pounds of heroin during a series of raids, Santa Rosa police said.

Amid a nationwide epidemic of opioid abuse that reaches into every region of the United States, the confiscation of 6 pounds of heroin is both sobering and likely predictive of continued seizures, Santa Rosa Police Lt. John Cregan said.

“It’s a rather significant drug seizure, to have over 6 pounds of heroin,” Cregan said.

Those jailed in the case included two Cotati men, one later released, and an East Palo Alto resident believed to have been making weekly deliveries of heroin to the Sonoma County area for local distribution, police said.

Detectives already had authored search warrants for their primary suspects, Cotati resident Jesus Ivan Camacho-Cardenas, 23, and East Palo Alto resident Juan Rodales-Becceril, 36, when they began surveillance on the latter man sometime Wednesday, police said.

Investigators tailed Rodales-Becceril when he left his South Bay home and drove to the North Bay, authorities said.

They followed him to Camacho-Cardenas’ Cotati home, suspected to be a base of sales operations, police said, and took the two men into custody, as well as a third man, Ricardo Martinez-Jimenez, 23.

During a search of Rodales-Becceril’s car they found about a pound of heroin, and in the Cotati house they found about a quarter-pound more, Cregan said.

With the assistance of East Palo Alto police, Santa Rosa detectives also searched Rodales- Becceril’s home as well as a rented storage unit, where they seized about 4 pounds of heroin, as well as packaging, scales and other evidence of drugs trafficking, authorities said.

“One of the sad realities that we’re seeing all across the nation and here in Sonoma County is a dramatic rise in opioid-related use in heroin and prescription drugs,” Cregan said.

“I think we’re going to be seeing more and more of these large seizures.”

Rodales-Becceril was arrested for suspected possession and transportation of heroin for sale and was booked Wednesday into the Sonoma County Jail, with bail of $500,000.

Camacho-Cardenas was booked early Thursday morning for suspected possession of narcotics for sale with an enhancement. His bail was $100,000, according to jail records.

Martinez-Jimenez spent two days in jail but was being released Friday afternoon after prosecutors declined to file charges against him in the case, authorities said.

You can reach Staff Writer Mary Callahan at 707-521-5249 or mary.callahan@pressdemocrat.com. On Twitter @MaryCallahanB.