YANKTON, S.D. (AP) — A grand jury in South Dakota has indicted a man accused of killing his girlfriend and dumping her dismembered body in a river in Michigan's Upper Peninsula.

The state Attorney General's office says 45-year-old Stephen Falkenberg has been indicted on first-degree manslaughter and second-degree murder in the March 1 death of 46-year-old Tamara LaFramboise.

Prosecutors say Falkenberg killed LaFramboise in Yankton, where they both lived, then drove to Menominee County, Michigan, where he grew up. Authorities say he discarded LaFramboise's dismembered body in the Little River, where two boys found it March 16.

A probable cause affidavit says Falkenberg told his sister he argued with LaFramboise, pushed her and she hit her head and died. Defense attorney Clint Sargent says Falkenberg plans to plead not guilty.

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