GALENA, Mo. (WWJ/AP) – A 19-year-old man has been sentenced to life in prison for the 2013 deaths of a Michigan couple.

Anthony Zarro, of Spring, Texas, will not be eligible for parole for at least 39 years. He pleaded guilty earlier to two counts of murder.

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Prosecutors say Zarro was 16 when he and Christopher Allen, then 15, killed Paul and Margaret Brooks, of Baldwin, Michigan, in their vacation cabin near Lampe, Missouri.

The two had run away from a southwest Missouri juvenile rehabilitation camp near the Brooks’ cabin two days before the couple were beaten and stabbed to death. Investigators believe they broke into an unoccupied home next to the Brooks’ and stayed there before the killings occurred.

The teens were arrested after a neighbor called police to tell them he was holding two young men at gunpoint after confronting them for suspicious behavior. When deputies arrived on the scene about 15 minutes later, they reportedly asked the teens if there were other people in the house, and Zarro said yes, “I killed them. I beat them with a baseball bat and stabbed them.”

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Police say further investigation revealed that the killings likely occurred in the kitchen, and then the bodies were moved to a bedroom. Police also said it appeared that the teens tried to clean up the crime scene.

Allen, of Nashville, Tennessee, is scheduled for trial in April on first-degree murder, armed criminal action and other charges, according to The Springfield News-Leader.

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