SIOUX FALLS, S.D. (AP) — A South Dakota man accused of killing his girlfriend and dumping her dismembered body into a river in Michigan's Upper Peninsula is due in court.

Stephen Falkenberg is scheduled for an initial appearance in Yankton County court Thursday in the death of Tamara LaFramboise. Defense attorney Clint Sargent says Falkenberg will plead not guilty to a second-degree murder charge. Prosecutors say Falkenberg killed LaFramboise in Yankton where they both lived.

Authorities say Falkenberg drove to Menominee County, Michigan where he grew up and discarded the victim's dismembered body in the Little River where two boys discovered it Saturday. The woman's head, hands and feet have not been found.

A probable cause affidavit says Falkenberg told his sister he had an argument with LaFramboise at her Yankton apartment and that he pushed her, she hit her head and died.

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