A federal law enforcement source confirmed that Pima County Sheriff Chris Nanos is declining to provide the FBI with critical evidence tied to the disappearance of Nancy Guthrie in Tucson, Arizona.

According to information first reported by Reuters, the materials sought by federal authorities include a glove and DNA recovered from inside Guthrie’s home. The FBI requested the items so they could be analyzed at the bureau’s national crime laboratory in Quantico, Virginia.

Instead, Nanos has insisted the evidence be sent to a private laboratory in Florida, where the sheriff’s office maintains a contract for forensic testing, the source said. The federal source added that Pima County has spent roughly $200,000 to send evidence to the Florida lab as part of its contractual arrangement.

“It risks further slowing a case that grows more urgent by the minute,” the federal official told Reuters, pointing to what were described as earlier setbacks in the investigation. The source also criticized local authorities for not seeking federal assistance sooner.

The Pima County Sheriff’s Office remains the lead investigative agency in the case. Under standard protocol, the FBI may participate only at the request of local officials.

“It’s clear the fastest path to answers is leveraging federal resources and technology. Anything less only prolongs the Guthrie family’s grief and the community’s wait for justice,” the official said.

The reported disagreement comes as tensions appear to be emerging between federal and county investigators while the search approaches the two-week mark.

Earlier this week, authorities released surveillance footage showing a masked individual approaching Guthrie’s front door shortly before she went missing. She disappeared from her Tucson residence in the early morning hours of Sunday, Feb. 1, and was reported missing later that day.

The FBI has increased the reward to $100,000 for information leading to her return or to an arrest.