A woman who wanted to adopt an Arizona baby that's been missing for more than a month has been arrested.

Tammi Smith was arrested Tuesday at her Scottsdale home on charges of custodial interference, conspiracy to commit custodial interference and forgery.

Smith and her husband Jack Smith have been considered "persons of interest" for weeks in the investigation into the disappearance of 8-month-old Gabriel Johnson of Tempe. Jack Smith did not answer his cell phone, and his voicemail box was full.

Gabriel's mother, 23-year-old Elizabeth Johnson, was arrested Dec. 30 in Florida and is charged in Arizona with kidnapping, child abuse and custodial interference.

Tempe police Sgt. Steve Carbajal says Smith would be booked later into Maricopa County jail.

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