Federal agents are digging up mass gravesites at a Humboldt County animal rescue where 730 of 900 transferred dogs remain unaccounted for — while the owner has issued a public statement defending every death as necessary.

Two weeks after The Dissent revealed that Oakland Animal Services paid $376,000 to Miranda's Rescue over four years while its owner allegedly shot Bay Area dogs and falsely reported them as adopted, the investigation has escalated sharply: the FBI and the U.S. Department of Agriculture have joined active excavations at the Fortuna property, and founder Shannon Miranda has gone on record for the first time to argue that each euthanasia decision was documented, justified, and made in the interest of public safety.

Humboldt County Sheriff William Honsal confirmed this week that investigators executing a second search warrant have uncovered multiple suspected gravesites during excavations of the pasture at Miranda's Rescue in Fortuna. "We have uncovered several anomalies in the soil, what we believe are gravesites amongst the pasture area," Honsal told NBC Bay Area. "We are going to continue to search there until we find all the graves that we possibly can."

The probe began in April when two witnesses provided video they said showed dogs being shot and buried on the property. Since then, dozens of animals have been recovered from mass graves. Of the roughly 900 animals transferred to Miranda's Rescue from shelters statewide between January 2025 and April 2026, 730 are currently unaccounted for, according to Honsal.

The case took on a personal dimension this week when Oakland Animal Services confirmed that microchip records identified one of its dogs — a dog named Zora — as having been shot and buried on the property, even though Miranda's Rescue had reported her as adopted. Oakland Animal Services has transferred more than 800 dogs to the facility since 2020.

Staff at the Oakland shelter recently planted a remembrance tree and dedicated a bench for the dogs they fear never received the second chance they had been promised. "I think that the owner and operator of this facility is held accountable to the greatest extent possible of the law — that is the greatest thing that could happen," said Joe DeVries, director of Oakland Animal Services. He added that the active federal investigation had given his staff a sense of renewed purpose: "It was uplifting. It really made the team feel like, OK, something is going to happen, that there will be accountability, that there will be justice in the end."

Meanwhile, Miranda went public with her account on June 18, posting a statement on the rescue's website that named Zora specifically. Miranda wrote that Zora had arrived heavily sedated, subsequently killed a feral cat during a walk with a prospective adopter, then broke free and attacked another dog. In a second case she described, a transferred dog had lunged at a stroller carrying an infant before staff intervened. She said these were "difficult decisions" made "based on my responsibility to protect both the public and the animals in our care," and that euthanasia decisions had been "notified to local authorities in advance."

The sheriff's office, however, says no such documentation can be found at the facility. "There's no adoption records, no records whatsoever that we can locate that Miranda's does not have that lets us know what happened to those animals," Honsal said. "That's what we are looking for right now."

The FBI and the U.S. Department of Agriculture have now joined local investigators, a significant escalation indicating potential federal charges — though Honsal said no charges have been filed and the owner is cooperating. Miranda's Rescue did not respond to a request for comment from NBC Bay Area beyond the website statement.

The search is expected to continue through the end of the week as investigators work to determine the full scope of what happened to the animals transferred to the facility — among them dogs that Oakland shelter staff had personally fostered for months before sending them north.

Miranda's Rescue is located at 1603 Sandy Prairie Road, Fortuna, CA. Anyone with information about animals transferred to the facility is encouraged to contact the Humboldt County Sheriff's Office.