A 15-year-old Utah boy was arrested Thursday after police claimed he killed his two younger siblings with a knife a day earlier.
The unidentified teenager is being held at the Farmington Bay Youth Detention Center in connection with the Wednesday murders of his little brothers, aged 4 and 10.
Police said the boys' mother returned home Wednesday from a dance recital with her three other children to find the bodies of her 4-year-old and 10-year-old sons. The 15-year-old, who was supposed to be watching his brothers, was missing when police arrived and was immediately labeled a person of interest.
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The teen was found later that night walking along an area street and was taken to a nearby hospital to be treated for minor injuries that were "consistent with this kind of attack,"
Davis County Sheriff Todd Richardson told the Desert News.
"He spoke pretty bluntly with our investigators," Richardson said. "We believe the suspect acted alone."
Two knives believed to have been used in the crime were also recovered from the home.
Police said they believe they know the boy's motive, but declined to say what it was.
"As time goes on, I think it will be released as to why he did what he did," Richardson said.
The teen, an honor student, was in the news briefly in 2011 when he ran away from home. He was later found at a Wendy's restaurant about four miles from his house.
But neighbors said he never seemed like the type of kid who would commit such a horrific crime.
"From what I understand, he's a model student, from what I've heard," neighbor Ann Durrwachter told the Desert News. "I've never had any complaints about him or his family. I always figured him as model 15-year-old that every mom dreamed of having. He was just carefree almost. He just kind of did his own thing as most boys do."
Another neighbor said the two brothers who were killed were adopted and the 15-year-old was his parents' biological son.
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"You could tell there was a sibling rivalry
between the biological son and the adopted boys," the neighbor told ABC4.com. "But I never imagined it could go this far."
Police said prosecutors will be screening the case against the 15-year-old, who will be charged in the juvenile system.
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