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An Orange County jury convicted an ex-U.S. Army soldier Thursday of three counts of murder for the shotgun slayings of a Fullerton couple and their friend in 2016.

Josh Acosta, left, and Frank Felix are shown in booking photos released Sept. 25, 2016, by the Fullerton Police Department.

Joshua Charles Acosta, 23, was found guilty of three counts of murder, along with the special circumstance of multiple murders and the special allegation that he personally used a gun in the crime. He faces life in prison without the possibility of parole at his sentencing hearing, scheduled for Dec. 14.

He was accused of carrying out the Sept. 24, 2016, killings with the help of co-defendant Frank Felix, 27, of Sun Valley, who is being tried separately for his alleged role in the killings.

Felix is accused of helping Acosta get a shotgun, driving him to the victims’ home and waiting outside in a truck while Acosta snuck into the house, the Orange County District Attorney’s Office said in a written statement. Inside were Christopher Yost, 34, his wife Jennifer Goodwill-Yost, 39, and their friend Arthur William Boucher, who was spending the night.

Victims Christopher Yost and Jennifer Goodwill Yost, left, and Arthur William Boucher are shown in family photos released Sept. 25, 2016.

“Acosta entered the living room and shot Boucher in the head as the victim slept on the couch,” the statement said.

“The defendant then went to the master bedroom and shot Goodwill-Yost in the face,” it continued. “Yost awoke and Acosta shot the victim in the head as he was fleeing outside.”

After the shooting, Felix and Acosta went to Felix’s home, where they attempted to destroy evidence, prosecutors said.

The killings were discovered when children of the victims found their bodies, authorities said.

Fullerton Police Department investigators arrested Acosta at his Army barracks in Fort Irwin, authorities said. Felix was found and arrested at his home.

Acosta was a mechanic in the Army, according to the Orange County Register.

Katlynn Goodwill, who was 17 at the time of the killings, testified that she had planned to run away with help from Acosta and Felix, but did not know they planned violence, the newspaper reported.

She testified that Yost, who was her step-father, had molested her for more than a decade, according to the Register. She said she told Felix about the abuse and asked for help in running away from home.

Goodwill’s parents had told her to stay away from Felix, she testified. She said Felix had blackmailed her into sex having sex with him by threatening to reveal the sexual abuse to her mother, the Register said.

Goodwill told the court she planned to tell her mother about the abuse and leave home the night the killings occurred, adding she had second thoughts, but felt pressured by Acosta to move forward with the plan, according to the publication.