On June 24, Paulette Larwinski was attacked near Indian School Road and Drinkwater Boulevard.
Larwinski was taken to a hospital in critical condition, but died a few days later as a result of her injuries, authorities said.
Jadyn Curtis was arrested on Thursday afternoon for first-degree murder, sex assault, kidnapping and armed robbery.
According to Scottsdale police, they received multiple tips from the public which led to Curtis’ arrest.
During the investigation, officials say they linked DNA evidence from the crime scene to Curtis, as well as video surveillance captured in the area around the time of the incident.
At the scene, police found a bloody rock and say Curtis appeared on surveillance video dragging Larwinkski's unconscious body, according to court documents.
A former high school classmate of Curtis's told ABC15 he was shocked to hear of the arrest.
"He was your average guy," said Robert Ferrara, who told ABC15 he played soccer with Curtis for roughly eight years. "I don't know what would cause him to do such harm to a person, especially an older lady."
"I just felt like it was important to make sure that everybody's honored for the life that they lived," said an emotional Allie Peters. "We don't know her story so I wanted to make sure that she was taken care of."