ALPENA, Mich. (AP) — A jury convicted a man of murder in the deaths of a teenage girl and a woman in northern Michigan, including one victim whose body was buried in a backyard.

Prosecutors alleged that Brad Srebnik killed 17-year-old Brynn Bills and subsequently killed his girlfriend, Abby Hill, because she knew what he did in the Alpena area during the summer of 2021.

Srebnik decided to stay in jail when the verdict was read Thursday in Alpena County court. He faces a mandatory sentence of life in prison.

“The murders of Brynn Bills and Abby Hill shocked the community, and it is our hope that these convictions may bring some peace and healing," Attorney General Dana Nessel said.

Bills was last seen in August 2021, shortly before she would have turned 18 years old. Her body was unearthed the following month in Joshua Wirgau’s yard in Alpena Township.

Hill, 31, was found dead in a wooded area that fall.

Wirgau was an important witness for prosecutors. He, too, was charged in Hill's death, but he agreed to a plea deal in exchange for a prison sentence that will make him eligible for parole.

Wirgau told jurors that Srebnik told him he had strangled Bills. Wirgau said he was present when Hill was fatally shot. Drug use appeared to be a common thread in the group.

Srebnik's attorney, Patrick Cherry, told the jury that Srebnik might have been framed by a drug dealer who didn't like Bills. Assistant Attorney General Danielle Hagaman-Clark said the theory was “garbage.”