ALEXANDRIA, Minn. (AP) - Prosecutors have dropped charges against an Alexandria man who served six years in prison for the death of his infant daughter.

Michael Hansen had been released from prison in August and was preparing for a new trial.

But in a statement Friday, the Douglas County Attorney's Office said it "no longer believes that it can prove the defendant's guilt beyond a reasonable doubt."

A jury found Hansen guilty in 2006 of second-degree murder in the death of his 4-month-old daughter, Avryonna. The baby died in 2004.

But a judge in July overturned Hansen's conviction based on evidence presented by the Innocence Project of Minnesota, which argued independent medical experts found that the baby likely died of accidental suffocation while she slept.

The new trial had been scheduled to begin Sept. 26.

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