It happened around 3:10 a.m. on the 200 block of South Broad Street outside of the DoubleTree Hotel.
Police said a 53-year-old man was stabbed in the arm. He was taken to the hospital in stable condition.
Investigators said they stopped a man who fit the description of the attacker in the area of Juniper and Locust streets and police are questioning him.
There is no word on a motive for the incident and there have been no arrests made at this time.
Anyone with information is asked to contact the police.