PORTLAND, Ore. (AP) — Authorities say a woman who went missing under strange circumstances has been found.

The Washington County Sheriff's Office says based on a tip, 23-year-old Demi Helenius was located at about 8:30 p.m. Tuesday in Roseburg, Oregon. The sheriff's office says she was determined to be safe and in good health.

KATU reports (http://bit.ly/2umwsk2 ) that Sgt. David Thompson with the sheriff's office had said Helenius never returned home after attending the Landmark Worldwide Forum at the Embassy Suites Hotel near the Portland airport Saturday night.

Thompson says Helenius' phone was given to a worker at a Dairy Queen in Creswell, Oregon, Saturday night by a man passing through the drive through.

Her car was found in Cottage Grove, about 10 miles south of Creswell on Interstate 5.

No further information was immediately released about her disappearance.