Police say a Dubuque man threatened his girlfriend’s son with a knife during a disturbance. 35 year old Joseph Evilsizer was arrested Tuesday at his residence on charges of first-degree harassment and assault. Reports say that Evilsizer threatened 23 year old Colton Puccio on Tuesday afternoon at the residence of Evilsizer and his girlfriend, 47 year old Tara Parker, who is Puccio’s mother. Puccio told police that he was completing some paperwork in the residence when Evilsizer became upset with him, grabbed a small pocketknife and approached Puccio in the kitchen with the blade opened.