A maintenance worker heard the victim screaming at the Pines at Arborwood complex around 9:30 a.m. and tried to intervene.
But police say by the time they arrived, the suspect had pushed himself back on top of the woman with his hands to her throat.
24-year-Ted Bockarie of Lindenwold was arrested and is being held on a million dollars bail on attempted murder charges.
The victim was taken to Cooper University Hospital where she is listed in stable condition.