HILLSBORO, Mo. (KMOX) -- Police in Jefferson County say a man killed his dad after his dad tried to intervene in a beating.Nicholas Smoot, 27, of Hillsboro is charged with second degree murder, armed criminal action and second degree domestic assault. He's accused of killing his father, Eric Smoot, 53.Nicholas was allegedly assaulting his live-in girlfriend when his father tried to stop it. Police say Eric Smoot was beaten with a golf club and was later pronounced dead at the hospital.Nicholas Smoot is being held without bond in the Jefferson County jail.© 2019 KMOX (Entercom). All rights reserved.