Officers were called to the 1500 block of Locust Street around 2:30 a.m.
That's where they found the victim, a 33-year-old woman, with serious injuries to her back.
The woman told police she got into an argument with a man she knows when he pulled a knife and stabbed her in the area of Broad and Locust.
The woman was able to run from her attacker and get help.
The suspect ran off in an unknown direction.
So far, no arrests have been made. The name of the suspect has not been released.