A Yankton County jury found a Yankton man guilty of second degree murder and first degree manslaugther. 45-year old Stephen Falkenberg killed 46-year old Tamara LaFramboise of Yankton in March of last year. Prosecutors said in court documents that Falkenberg told his sister he argued with LaFramboise, pushed her and she hit her head and died. Her body was discovered in a Michigan river about two weeks after the murder took place. Falkenberg could face life in prison when he is sentenced in March.