PITTSBURGH - A prosecutor said Monday that he had no choice but to file adult charges against an 11-year-old boy accused of killing his father's pregnant girlfriend, even though the child's age raises questions about where and how to jail him.

Lawrence County District Attorney John Bongivengo said Pennsylvania state law prohibits him from filing criminal homicide charges against Jordan Brown in juvenile court. As such, he had to charge the boy with homicide as an adult or with a lesser charge.

But he expects the boy's attorney to ask a judge to move the case to juvenile court.

Brown is charged with using his own 20-gauge shotgun - a Christmas present he used to win a turkey shoot on Valentine's Day - to kill 26-year-old Kenzie Marie Houk as she slept Friday morning. Houk was eight months pregnant with Brown's father's child, and had two daughters, aged 7 and 4, from a previous relationship.

To get the case moved to juvenile court, defense attorney Dennis Elisco must convince a judge the boy can be rehabilitated in that setting.

Bongivengo contends it was a "premeditated, cold killing."

"And because the juvenile system only has jurisdiction until he's 21, the last thing I want is a 21-year-old who's going to be out on the streets and willing to kill you."

Bongivengo said Houk's family has told police the boy had threatened her and her 7-year-old daughter in the weeks before the shooting. Houk's family has told The Associated Press the boy may have been jealous of Houk and her children.

"If this person were 18, we'd be looking at pursuing the death penalty," Bongivengo said.

The Associated Press could not immediately locate relatives of the boy and his father for comment Monday.

Elisco has said the boy hasn't confessed to the shooting and he doubts the physical evidence will support police's claim that the boy killed Houk execution-style, with one shot to the back of her head. Elisco didn't return phone calls Monday. He had planned to file motions asking a judge to move the case to juvenile court and to have the boy released on bail to his father.

Police have said after the shooting the boy then hopped onto a school bus with Houk's oldest daughter. State troopers picked him up at school after tree trimmers called 911 when Houk's youngest daughter told them she thought her mother was dead.

Brown and his father moved last year into a rural farmhouse Houk rented in Wampum, about 45 miles northwest of Pittsburgh. The couple were engaged in December.

A state police search warrant revealed Monday that police also found a blue blanket with a quarter-sized hole in it that appeared to be singed from a shotgun blast.

Bongivengo said authorities think the boy covered the gun with the blanket to hide it from Houk.

Because Brown is charged as an adult, he must remain in the county jail, and is separated from about 300 adult inmates. He's being kept out of a normal cellblock and in a 10-by-8-foot cell in the booking area and checked on every 15 minutes.

Lawrence County officials have checked to see if other counties have special jail facilities for underage offenders and, so far, haven't found any. Moving the boy to a juvenile detention center isn't possible because such facilities can't house anybody who is an "adult" in the eyes of the law, Bongivengo said.

Bongivengo said authorities will consider mitigating factors, like the boy's mental state and age, when Elisco files the motion to move the case to juvenile court. Bongivengo acknowledged concerns raised by experts interviewed by The Associated Press that the boy might have shot his stepmother-to-be be because he couldn't adjust to his new blended family, but said such conflicts don't normally result in murder.

"If it's such a huge problem you'd hear about it a heck of a lot more," Bongivengo said. "But to take this step, that's a huge step. This is something you don't see all the time. It's a rarity."

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