OREM — When David Driscoll contacted a family member, he confessed he had "done something horrible," a newly released search warrant states.

Driscoll, 37, had shot and killed his former fiancee, Brittany Engstrom, 27, in Orem on Dec. 28. Later that day, he took his own life in Saratoga Springs.

Engstrom was scheduled to testify in court against Driscoll during a preliminary hearing the next day. Driscoll was facing four counts of aggravated sex abuse of a child, a first-degree felony.

A no contact order was in place against Driscoll at the time of Engstrom's death, according to the search warrant affidavit filed in 4th District Court.

But just before noon on Dec. 28, Orem police responded to 1675 S. 400 East on a report of a woman screaming.

A neighbor told officers he could hear "yelling in the apartment across from (his)," and that "it sounded like the female was yelling at a child. They also could hear what sounded like a fire alarm … going off," according to the affidavit.

When officers knocked on the door, no one answered. They returned later and again no one answered. About 2:20 p.m., police received information that Driscoll had contacted a family member and said he had "done something horrible," the warrant states.

"David said he had been in an altercation with Brittany at her home earlier this morning, and in 'self-defense,' David said he shot Brittany several times in the back, killing her. David then collected the brass casings that had ejected from the firearm as to not leave them behind and left the home," the family member told police, according to the affidavit.

The search warrant was for cellphones and possible social media posts.

Police found Driscoll later that day in the parking lot of the Ranches Golf Club in Eagle Mountain after pinging the location of his cellphone. He shot himself after two hours of negotiations with officers who attempted to convince him to surrender.

Driscoll served in the Utah National Guard from 2006 to 2012 and in the U.S. Army from 1999 to 2005, according to friends.

A friend said Driscoll had been struggling with the criminal charges against him.

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