Police have confirmed that a 31-year-old man is now in custody.
Inspector McCullough said: “Just before 4am officers were called to reports of a serious assault in the Victoria Gardens area and an injured man.
“A second man who came across the attack chased after the suspect when he pulled out an object and stabbed him in the arm.
“The suspect in the attack then fled towards Antrim Road and was apprehended by police a short time later. He is currently in custody and assisting with the investigation.
“Our investigation is at an early stage and I would appeal to anyone who was in the Victoria Gardens and Antrim Road areas of Lurgan at this time and who may have witnessed anything to contact police on 101 quoting 372 of 08.07 .22 years old.” added Insp McCullough.
You can also contact Crimestoppers anonymously on 0800 555 111 or online at http://crimestoppers-uk.org/