Paula Anderson, 67, was rushed to WakeMed where she died. Officials said it was unclear whether someone shot her in the chest or in the back.
At least one neighbor heard the shot and someone walking a dog saw Anderson's body in the driveway.
"It's a very quiet neighborhood, so it was very disturbing, to wake up and see all the cop cars," neighbor Carrie Brojakowski told Eyewitness News.
Investigators recovered a gun at the scene and believe a single shot was fired.
Police said they detained a person of interest who they questioned at the Apex Police Department on Wednesday. That person has not been identified.
"We do have a person of interest that we are speaking with," Captain Ann Stephens of the Apex Police Department said. "There is no danger to the public. We feel like we know the person of interest we are speaking with knows the victim, and [is] familiar with the victim."
Anderson's husband, 91-year-old Thomas Anderson, reportedly lived in the home with his wife.
Eyewitness News has learned that Anderson had recently thrown a birthday party for her husband. Neighbors said he suffers from dementia, which she sought help caring for. They said he was currently staying with relatives.
Apex police said they did not receive any calls about a domestic disturbance from the home before the 911 communication.
Anderson was known as "Jean" to most friends and relatives.
Neighbors described her as a quiet lady who gave out the most candy on Halloween and was kind to everyone.