A Montana man who is charged in killing a German exchange student allegedly pointed a shotgun at a lawn care worker days before the fatal shooting.

Michael McMillan testified Friday that he arrived at Markus Kaarma’s home in Missoula to spray for insects back in April when he saw Kaarma, furious, come to the door naked and point a shotgun at him, asking what he was doing there, according to the Associated Press.

McMillan said he was “scared, frozen,” and that Kaarma’s girlfriend apologized and said he hadn’t gotten much sleep because of some recent burglaries. Just four days later, police say Kaarma shot and killed 17-year-old foreign exchange student Diren Dede after a motion detector in his garage alerted him to someone’s presence. Defense attorneys are arguing that he acted in self-defense, invoking Montana’s “stand your ground” law, which allows people to use deadly force if people believe they are going to be threatened with harm.

Kaarma, 30, said he had no idea who the intruder was or whether the person was armed, and felt anxious for the safety of his girlfriend and his infant son since their home had been burglarized twice recently.

On the same day of Kaarma’s encounter with the lawn care worker, Kaarma went to get a haircut and people at the shop testified they heard him talk about waiting to shoot an intruder. College student Louis Richman also said he overheard Kaarma discuss shooting burglars and said he believed him to be watching porn on his phone as they waited for haircuts. However, he said he didn’t think he would actually shoot someone.

In the 911 call played for jurors, Kaarma’s girlfriend said Dede was lying face down and “barely breathing” after the shooting, and Kaarma did not try to help. He died shortly after at the hospital.

Kaarma is charged with baiting the victim into sneaking into the garage and then shooting him four times with a shotgun. Kaarma allegedly admitted to police officers who arrived on scene that he had been the shooter.

Kaarma’s grilfriend allegedly told police afterward that Dede had pleaded for his life before the shooting.

The trial is set to continue through Dec. 19.