WAMPUM, Pa. -- An 11-year-old boy was arrested early Saturday morning and charged in connection with the shotgun slaying of his father's pregnant girlfriend in Wampum, Lawrence County.

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State police took Jordan Anthony Brown into custody shortly before 3 a.m. He was being held in the county jail, charged as an adult with the homicides of Kenzie Marie Houk and her unborn child. A preliminary hearing is scheduled for Thursday.

"This is something you wouldn't even think of in your worst nightmare," said Lawrence County District Attorney John Bongivengo, adding that "the whole situation is heinous."

Houk, 26, was found dead Friday morning by her 4-year-old daughter at their farmhouse on Wampum New Galilee Road.

State Trooper Michael Markey said the girl ran outside and told employees of a tree-cutting service that her mother was dead. The workers then called 911.

"Something like this, this close to home, it affects all us mothers," said neighbor Tina Potter.

As residents recovered from the shock of what happened inside the farmhouse, the suspect's father was pushing to have his son released on bail.

His attorney met with Brown this weekend and doesn't believe the child is responsible for killing Houk and her unborn baby. But the Lawrence County district attorney said there is more than enough evidence.

Police said that when brown was questioned he provided false leads. They said it was Houk's 7-year-old daughter who gave investigators major clues.

"She saw him with what she believed was a shotgun and heard a loud bang," Bongivengo said.

Houk's father, Jack, said he hurried to the house after getting a phone call from her boyfriend.

"I said, 'Will you please tell me what's going on?' and he says, 'I can't, you got to get down here immediately,' so I raced down here and police told me that my daughter's passed away and the baby also," Jack Houk said.

Video: Father: 'Who Would Be Crazy Enough To Do That?'

Bongivengo said that Houk was shot in the back of the head as she lay in bed Friday morning.

Police said the weapon was a .20-gauge "youth model" shotgun, which investigators found in the boy's bedroom.

Bongivengo said that the boy and Houk's 7-year-old daughter -- who was also home at the time of the shooting and heard the shot -- both went to school afterward.

Brown's father -- the live-in boyfriend of Houk and the father of her unborn son -- was at work when the shot was fired, police said.

At this time, police don't have a motive.

"Usually you hear of murders happening in California or some where like that, not in little towns," said neighbor Donna Simmons.

No charges have been filed against the father. The district attorney said the type of shotgun used doesn't require registration.

Houk's two daughters are staying with their maternal grandparents.

Brown is in the Lawrence County Jail. He could face life in prison if he's charged as an adult and found guilty.

Houk was 8 months pregnant. She was expected to deliver a boy in early March.

"It hasn't really set in yet. It's going to be tough," Jack Houk said.