MISSOULA, Mont. — A suspect has been arrested in Montana in connection with the fatal stabbing of a 22-year-old Portland mother in October 2023.

Connor J. O'Brien, 21, was arrested Monday in Missoula by the Montana Regional Violent Crimes Task Force and Missoula Police Department, according to the Portland Police Bureau.

O'Brien faces charges of second-degree murder and unlawful use of a weapon in the death of Tiara Atencio . He is being held in the Missoula County Jail awaiting extradition to Oregon.

Atencio was stabbed to death on Oct. 19, 2023, in the 6800 block of Southeast Powell Boulevard in Portland's South Tabor neighborhood. She died from her injuries at a hospital, leaving behind a toddler with special needs.

According to a 2024 report by KGW , Atencio had spent the e

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