NEW ROCKFORD, N.D.-A Shakopee, Minn., woman will spend nearly 20 years in prison for her role in the death of a woman whose body was found two years ago in the Sheyenne River.

Crystal Marie Herman, 38, was sentenced Thursday, May 10, in Eddy County District Court after pleading guilty to a Class AA felony of accomplice to murder for the death of 36-year-old Amanda Engst. The crime carries a life sentence without parole, but a plea deal lowered the sentence.

Engst, a Breckenridge, Minn., native, lived in Fargo; Halstad, Minn.; and Warwick, N.D., before she went missing in the fall of 2015. Her body was recovered in February 2016 from the Sheyenne River south of Warwick on the Spirit Lake Indian Reservation. Investigators later ruled her death a homicide.

Herman and her husband, 38-year-old Billy Jo Herman, were connected to Engst when investigators arrested the couple for a string of robberies in Minnesota and North Dakota. Officers said they found Engst's vehicle in their possession.

The Hermans are serving time behind bars for the robberies, which happened in late October 2015, according to Forum News Service archives. Court documents filed in Eddy County District Court said Crystal Herman helped her husband kidnap Engst on or about Oct. 13, 2015.

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"In the course of and in furtherance of the crimes or of immediate flight therefrom, the defendant and/or Billy Herman caused the death of Amanda Engst," according to the criminal complaint.

Prosecutors said Crystal Herman opened a car door and allowed her husband to strangle Engst. Billy Herman, who has not been charged in the case, then allegedly beat Engst with a shovel, according to court documents.

Crystal Herman was credited 183 days for time served.