Pittsburgh Bureau of Police officers from Zone Two responded to reports of a stabbing in the Market Square area Downtown just before 11 p.m.
When they arrived on scene they found a male victim with lacerations to his arm and back near 2 South Market Square.
He was transported by EMS to a local hospital in stable condition.
One male suspect is in custody. Charges are pending.
Police believe the initial incident may have occurred in the 700 block of Liberty Avenue with the victim either fleeing or being chased into Market Square by the suspect.
The investigation continues.
UPDATE: Michael Bob Jr., 25, of Carnegie, PA was arrested in this incident. He is charged with Aggravated Assault and Terroristic Threats.