SALT LAKE CITY (AP) -- A 21-year-old father was upset when his girlfriend broke up with him and plotted for a month before killing his infant son with a rifle, authorities said Monday.
Joshua Petersen of American Fork was denied bond and ordered held as prosecutors prepare formal charges, which are expected next Monday.
It's "extremely" rare for a Utah judge to hold a defendant without bail, said prosecutor Craig Johnson, who put a police sergeant on the stand Monday to underscore the serious allegation against the father.
Sgt. Gregg Ludlow broke down when he described how Ryker Petersen died of a gunshot to the head, and how Petersen revealed to investigators that he had planned the killing, Johnson said.
A booking statement said Petersen sat his son down on a sofa in the basement, left the room to load his rifle, and returned to shoot the boy in the forehead.
Petersen then sought to turn the .22-caliber rifle on himself but was stopped by a family member, police said. He likely faces a charge next week of aggravated murder, which could bring the death penalty if he's convicted, Johnson said.
Family members tell Utah news outlets that Petersen was suffering from lifelong depression and also was hurting over the breakup of his relationship with the boy's mother.
Amanda Merrill Pilling decided to end the relationship days before the shooting, according to her mother.
"She finally kicked him out," Tawnya Judd, the boy's grandmother, told KSL-TV. "She said, 'Mom, you'll be proud of me. I finally told him I'm never going back.'"
Judd speculated that Petersen acted out of fury by shooting his son.
Police declined comment Monday, referring The Associated Press to the Utah County Attorney's Office.
Petersen does not have an attorney, Johnson said.
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