TUCSON, Arizona — Frustrated volunteers have taken the search for Nancy Guthrie into their own hands — combing the garbage-filled desert ditches and homeless camps near her home for clues. And on Sunday,

Investigators returned to Nancy Guthrie's Tucson neighborhood as the search for the missing 84-year-old entered its 22nd day.

The search for 84-year-old Nancy Guthrie began after she was abducted from her home near Tucson, Arizona, early on Sunday, Feb. 1, authorities said.

Pima County Sheriff Chris Nanos revealed that there are problems with the DNA evidence collected from Nancy Guthrie’s house that could take up to a year for the private Florida lab he’s using to resolve.

The following is a chronology of key developments in what authorities describe as the abduction of Nancy Guthrie, the 84-year-old mother of NBC's "Today" show co-anchor Savannah Guthrie. She was last seen by family members on January 31 after spending the evening at the Tucson home of her older daughter,

​Nancy was last seen at her home on January 31 and was reported missing the following day. Officials still have yet to name any suspects in the case and are offering a $100,000 reward for information related to Nancy’s whereabouts and her suspected kidnappers.

TUCSON, Airzona — Cops investigating the disappearance of Savannah Guthrie’s mom Nancy searched a septic tank behind her house Sunday, with drone footage showing them opening a manhole cover in the backyard.

An Arizona couple reported that they found a pair of blood-stained gloves and a rock with a dried blood droplet a mile from Nancy Guthrie's home.