A 36-year-old man, Justin Tyler Grandstaff, was arrested at the Border Patrol checkpoint south of Tucson in connection with the killing of two women in Arivaca early Thursday morning.
According to the Pima County Sheriff’s Department, deputies went to a home in Arivaca after reports of gunshots on Thursday, October 15, 2020, at approximately 1:08 a.m.
While en route to the 17000 block of West 3rd Street, deputies learned there were two female gunshot victims.
One of the female gunshot victims was 33-year-old Kaycie Mattias. She was pronounced deceased on scene. The second female, 55-year-old Monica Gilkey, was transported to a local hospital via ambulance, where she succumbed to her injuries and was pronounced deceased.