(CNN) A 43-year-old Iowa hog farmer was found guilty on Monday for murdering his wife with a corn rake.

In November 2018, Todd Mullis told authorities his wife, Amy Mullis, had fallen at the family farm in Earlville, Iowa, CNN affiliate KCRG reported.

But Dr. Kelly Kruse, who performed the autopsy on Amy's body, said the cause of death was sharp-force injuries of the torso.

"Homicide," she said in her testimony, recorded by Court TV.

Kruse testified that she observed multiple puncture wounds throughout Amy's upper body -- including injuries which she believes came from a corn rake. She said the wounds indicated Amy had been punctured at least twice with the rake.

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