Spokane County Sheriff's deputies said the youths -- ages 13 and 14 -- allegedly beat one of the two boys' mother in a drug-addled plot to kill the woman and then eat her liver.
"I think that was their original plan, to cut her open, but then they changed their minds," Deputy Craig Chamberlin told CNN Friday.
"The 14-year-old came up with the idea of, 'Hey, let's rip her open and eat her liver,' but it never happened," said Chamberlin.
The woman, whose name was withheld, was hospitalized in fair condition with multiple head injures.
The alleged incident occurred Tuesday. Deputies responding to a call found the bloodied woman in her home, where there was no sign of forced entry.
The two suspects were also booked in connection with an alleged hit-and-run traffic accident and a break-in during which another home was extensively damaged.
Chamberlin said one of the suspects admitted he and his cohort had been downing unidentified blue pills prior to their alleged crime spree.
"It could be anything, it could be ecstasy, it had to have been some type of opium, hallucinogen," he said. "We were never able to collect any."
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