A former Marine on trial for killing a woman and injuring a man in his Lowertown apartment laughed while he called 911, according to a recording played in court Wednesday.

Scott A. Klund, 30, of St. Paul is charged with second-degree murder with intent for killing Charlotte A. Rawls, 52, and attempted second-degree murder with intent for shooting Ray Gruer and slicing his throat on May 7, 2016.

"Who shot him?" 911 dispatcher Beth Krengel asked Klund three times.

"Uh, I did," said Klund, who sounded emotionless.

"Why did you shoot him?" Krengel asked.

Klund laughed and giggled loudly while Gruer, 31, cried for help in the background as he lay on the bathroom floor. Authorities said that Klund riddled the bathroom door with more than 20 bullet holes in an attempt to harm Gruer, who had sought refuge inside after Klund shot Rawls.

"You're good, bud," Klund apparently said to Gruer. "You're OK."

Klund turned his attention back to the dispatcher.

"I'm trying to keep him alive, and he is bleeding everywhere," Klund said.

Another dispatcher asked Klund where the man was hurt. "All over," Klund said.

Klund, who was honorably discharged from the U.S. Marines, had been drinking at the Bulldog Lowertown and ran into Rawls and Gruer about 2:45 a.m. at a nearby SuperAmerica gas station, Assistant Ramsey County Attorney Thomas Ring said in his opening statement.

Klund invited the homeless duo back to his third-floor apartment in the 200 block of 5th Street E. near Mears Park, where he used a "military-grade assault rifle" to shoot them, Ring told jurors.

"What police encountered can only be described as carnage and savagery," said Ring, who did not provide a possible motive for Klund's actions.

Klund's story that Gruer tried to take his computer is not believable, Ring argued, adding that even if it were true, Klund's "way over the top" reaction was unjustified.

One of Klund's two attorneys, Aaron Haddorff, said in his opening statement that Rawls and Gruer targeted Klund as an easy mark. The two were high on meth and desperate to make money. Gruer tried to sell Klund a speaker. They forcibly entered his apartment.

Haddorff told jurors that Klund did not resist because he was in a friendly mood that night. But Rawls began rifling through Klund's bedroom, and Gruer grabbed a knife and Klund's wallet, he said.

When Gruer ignored repeated orders to leave, Klund's military training kicked in and he escalated his verbal orders until he felt the need to shoot the two in self-defense, Haddorff argued.

"[Klund] began to clear his own apartment as if he was in a house in Afghanistan," Haddorff said.

Gruer was aggressive, the defense argued. "[Klund] does not have a duty to retreat" in his own home, Haddorff said.

St. Paul police investigators testified that authorities found an empty AR-15 rifle on Klund's bed, and that bullets traveled through a window and struck a building across Wacouta Street. Bullets also penetrated two nearby apartments. No one else was injured.

Haddorff told jurors they would "hear" from Klund, but declined to clarify if that meant his client would testify.

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