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. (AP Photo/Morrison County Sheriff's Office, File)

By AMY FORLITI Associated Press

A Minnesota man who killed two teenagers who broke into his home can be heard on an audio recording talking to himself for hours after the shooting and at one point, apparently describing the slain teens as "vermin."

Byron Smith, of Little Falls, faces first-degree premeditated murder charges in the deaths of 18-year-old Haile Kifer and 17-year-old Nick Brady on Thanksgiving Day in 2012. Smith, 65, claimed he was defending himself and feared for his life after several break-ins at his home.

Prosecutors, though, say Smith planned the killings. They say he sat in a chair in his basement and waited for the teens to enter his home, instead of calling police. Smith waited a full day after he shot them before asking a neighbor to call the authorities.

The killings stunned this central Minnesota community and stirred debate about how far people can go to defend their homes. 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.

Authorities who searched Smith's home after the killings testified Wednesday that they found an audio recorder that was turned on and an operating video surveillance system. The recorder was sitting on top of books on a bookshelf, near a chair where prosecutors say Smith waited for the teens.

In the recording, Smith can be heard breathing heavily and whispering. At one point, he said: "I don't see them as human. I see them as vermin."

The recording also captured the actual shootings, including Kifer screaming after she was shot. Janet Nelson, a special agent with the Bureau of Criminal Apprehension, testified that the full recording was six hours, 24 minutes long. She condensed it into 29 minutes of highlights, enhancing volume in some areas, and cutting background noise in others.

The tape was presented to jurors as a sequence of events, but defense attorneys raised questions about the recording on cross-examination, noting it had been spliced and altered, and some key pieces of information were left out.

The recording presented in court apparently starts before the shootings, with Smith talking about having someone come over and giving instructions on where to park. Smith also is heard saying: "I realize I don't have an appointment, but I would like to see one of the lawyers here."

The next sound played in court was the sound of glass shattering, followed by footsteps and heavy breathing. The recorder captured the sounds of Smith shooting Brady as he came down the stairs, including a groan from Brady after the first shot. A total of three shots were fired, and Smith can be heard saying "You're dead."

Then, there is rustling, several more thumps, clicks, and heavy breathing. The criminal complaint says Smith placed Brady's body on a tarp and dragged it into another room, then sat down and reloaded his weapon.

Kifer then comes down the stairs. More shots are fired, and Kifer screams. Then Smith said: "You're dying." Another shot was heard soon after. In a statement to investigators, Smith called it a "finishing shot."

Then, Smith whispers: "I'm safe now," according to the recording.