LITTLE FALLS, Minn. - Two teenage cousins killed after breaking into a Minnesota man's home were shot a total of nine times, with some shots coming from close range, a medical examiner testified at the man's murder trial Thursday.

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.

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. Prosecutors also 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.

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Dr. Kelly Mills with the Ramsey County Medical Examiner's Office testified that Brady was shot three times, Kifer six times. The final shot to Brady, which went through his hand and into his right temple, was the "most immediate fatal," Mills said. She described it as a close-range shot.

Kifer also was shot in the head at close range, Mills testified. She said the shot that killed Kifer, the fifth fired by Smith, was a close-range shot behind her left ear.

Mills also said Brady tested negative for drugs and alcohol. Kifer's toxicology tests showed the presence of a substance in cough medicine, as well as a marijuana metabolite that Mills says had no hallucinogenic effects. The question of possible drug use became an issue after the killings as Smith's friends claimed the teens were high on drugs, and authorities said a car linked to Brady and Kifer contained prescription drugs that had been stolen from another house. However, the drugs won't be allowed as evidence in court.

Defense attorneys were expected to cross-examine Mills on Thursday afternoon.

The killings stunned Little Falls, a central Minnesota community of 8,000, and stirred debate about how far people can go to defend their homes.

Earlier this week, prosecutors played for jurors an audio recording Smith made of the shootings. 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 contending some key pieces of information were left out.