A Walnutport man is being sought for an assault incident which occurred Thursday morning in which he fled the scene, jumped into the Lehigh River, and was the subject of a manhunt for several hours.

State police at Lehighton identified the suspect as John Duncan Holzer, 39, of 4458 Mountain View Drive.According to troopers about 8:30 a.m. Holzer allegedly physically assaulted his girlfriend, only identified by troopers as a 37-year-old, while driving from Weissport to East Penn Township along SR248.As the assault went on the female called 9-1-1 from her cellphone. Palmerton police responded and approached the vehicle along 248. At this point Holzer fled the vehicle and jumped into the Lehigh River.Holzer was then observed across the river and entering a wooded area leading onto the Appalachian Trail. Several state police units responded to the area and a search was conducted for several hours.As of presstime today Holzer has not been located. Troopers have obtained an arrest warrant for him charging him with simple assault and related counts.Anyone with information concerning the whereabouts of Holzer is asked to call troopers at (610) 377-4270.