(Vancouver, WA) -- New details are coming to light about the victim of a fatal Halloween shooting during a trick or treat event inside a shopping mall in Vancouver. The Seattle Times reports 26-year-old James Perez was the son of a man who was shot and killed by Portland police while unarmed two decades ago. Perez was six years old when Officer Jason Sery shot his father James Jahar Perez multiple times during a traffic stop in 2004. Police have arrested 32-year-old Travis Ward for the shooting of the younger Perez on the night of October 31st. Court records state Ward was wearing a "Joker" mask when he followed Perez to the food court of Vancouver Mall and shot him in the back of the head at point-blank range. Ward was at the mall with his mother, his girlfriend and his young daughter, who was dressed as a princess for trick or treating.