Morrison County Sheriff's Office
FILE - This Nov. 23, 2012 file photo provided by the Morrison County sheriff's office shows Byron David Smith, a Minnesota man accused of killing two teenagers who broke into his home in November last year. The Little Falls man who claimed he was defending his home from teens who had been terrorizing him for months goes on trial Monday, April 14, 2014, for their murders.

LITTLE FALLS, Minn. — A Minnesota man on trial for killing two teenagers after they broke into his house had been lying in wait in his basement with a book, some snacks and two guns, a prosecutor said Monday in his opening statement.

Byron Smith, 65, of Little Falls, is charged with first-degree premeditated murder in the slayings of 17-year-old Nick Brady and 18-year-old Haile Kifer on Thanksgiving Day in 2012. The killings rocked the small central Minnesota town of about 8,000 and stirred debate about how far a person can go in defending their home.

Smith has claimed self-defense, saying he feared the teens were armed and he was on edge after earlier, repeated break-ins at his home. Under Minnesota law, a person may use deadly force to prevent a felony from taking place in one's home or dwelling, but authorities have said Smith crossed a line when he continued to shoot the teens after they were no longer a threat.

Assistant Washington County Attorney Brent Wartner outlined for jurors Monday the evidence that prosecutors will present, including Smith's statements and audio from a recorder that Smith had set up in a bookcase the day of the break-in.

"He's down in the basement, in a chair, tucked between two bookcases at the bottom of the stairs. He said he was down there reading a book ... with his Mini-14, a .22-caliber revolver, some energy bars and a bottle of water," Wartner said.

Wartner said Smith heard the door of his house rattle at about 12:30 p.m., then someone walking across the deck, then a window breaking.

"And he waited," Wartner said.

As Brady descended the basement steps, Smith shot him in the chest, then in the back while Brady fell, Wartner said. Smith fired a final shot into Brady's head, the bullet passing through Brady's hand, Wartner said.

Smith put Brady's body on a tarp, dragged it into his workshop, reloaded his Mini-14 rifle and sat down again, the prosecutor said. A few minutes later, Kifer walked down the stairs and Smith shot her, Wartner said. He tried another shot, but his rifle jammed, Wartner said, and Smith told police he believed Kifer laughed at him.

"He was angry," Wartner said. "So he pulled out his revolver and he shot her twice in the head, once in the left eye and once behind the left ear."

Smith dragged Kifer's body into the workshop and laid it on top of Brady's. Smith told investigators he thought he heard Kifer gasping, so he pulled out his revolver for what he told police was a "good clean finishing shot to the head," the assistant prosecutor said.

Smith's attorney, Steve Meshbesher, was to present his opening statement later Monday.

Smith is a retired security engineer for the U.S. Department of State. Kifer and Brady were cousins. The two were well-known in the community, and both were involved in sports.

After their deaths, authorities said a car linked to Brady and Kifer contained prescription drugs that had been stolen from another house, apparently the day before they were killed. Court documents from another case show Brady had burglarized Smith's property at least twice in the months before he was killed.

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