Nancy Guthrie, an 84-year-old woman from Tucson, has been missing for 100 days with investigators unable to identify any suspects or achieve a significant breakthrough in the case.

The investigation has yielded limited evidence, including DNA material and doorbell video footage, according to reports. However, authorities have indicated there have been no major developments in determining what happened to Guthrie or her current whereabouts.

Sheriff's officials have stated there is "nothing new" to report in the case as it reaches this milestone. The lack of progress has prompted volunteer search groups to seek involvement in the search efforts, though their participation in the investigation remains unclear.

Guthrie disappeared from her Tucson residence, but the specific circumstances surrounding her disappearance have not been publicly detailed. The case represents one of numerous missing person investigations affecting elderly individuals across the country.

As the investigation continues into its fourth month, law enforcement agencies are presumably continuing to analyze available evidence and pursue leads in hopes of determining Guthrie's fate and location.