Police said it happened around 6 p.m. Wednesday at the Glen Royal Mill Apartments in the 800 block of North Main Street.
A caller told an emergency dispatcher that there had been an accidental stabbing.
However, it wasn't the first time a 911 call had been made from the apartment in question.
When police arrived, their primary concern was getting 23-year-old Cunningham to the hospital, but investigators apparently weren't satisfied with what they heard and saw at the scene.
Neighbors said Cunningham lived with his girlfriend and her daughter in apartment 218. They also said the couple fought frequently.
That claim was backed up by Wake Forest police. They told ABC11 that they had been called to the apartment a dozen times in the past year alone. All the calls were for domestic disturbances.
Here's how the crime was called in to 911:
Caller: "According to his girlfriend, he tripped over a box and fell onto the knife. He didn't know that the knife was in the box. "
911 operator: "Is the knife still in his chest?"
Caller: "Uh, (unintelligible)."
911 operator: "Make sure you leave it there, OK."
Caller: "The knife is already out. He fell on it and came back off of it."
ABC11 has not been able to determine the identity of that caller. However, we did receive this message in an email: "I did not say the knife was in a box I said in a pile of clothes. Also, not all the times the police went there were for domestic disturbances some were nuisance calls. Don't you think he would have been locked up for domestic violence if there were proof of that? Don't make a dead man out to be the monster."
Meanwhile, a neighbor told ABC11 that he saw Cunningham drunk or stoned, or both, before the stabbing incident.
Another neighbor said if Delgado killed Cunningham it was self-defense.
A former co-worker who urged Delgado to go to police agrees.
"I was surprised that it was him and not her," said Keith Conley. "That's what surprised me."
Messages to Cunningham's family were not returned to ABC11.