(CNN) -- What would compel a 15-year-old girl and her 11-year-old sister to allegedly shoot to death their older brother?
Some mean treatment, they told police.
The older girl claimed her brother had beaten her and locked her in her room. When he fell asleep, she got a gun out of her parents’ room and shot him, according to a police report obtained by CNN affiliate WJAX.
The 11-year-old allegedly assisted her, authorities said.
Both girls have been charged with premeditated murder and are to appear in a Florida court on Wednesday along with their parents.
The two inadvertently tipped off an officer to the Monday shooting, when they left their Columbia County home and walked to the town of White Springs nearly four miles away.
The 11-year-old called a friend’s mother to tell her that she had run away. After the friend’s mother arrived, she called police.
An officer came, and at first, the older girl played it cool, putting on makeup while answering some questions and dodging others, the report said.
But then she broke into tears and told the officer about her brother.
Body in living room
Police contacted the county sheriff. That evening, deputies went to the family’s home to investigate. They found the 16-year-old boy’s body on the living room floor.
The children’s parents, Keith and Misty Kornegay, were out of town on a truck driving job, WJAX reported, but returned immediately when they received the news.
The three children and an additional 3-year-old daughter had been unsupervised.
The parents were also arrested and charged with child neglect, the county sheriff’s office said. The toddler is being cared for by a child protection agency.
The case is still under investigation.
While police have identified the girls, CNN is withholding their names since they are minors and have not been charged as adults.
In 2010, the sheriff’s office visited the home on reports of vandalism and a civil matter, WJAX reported.
Killings are uncommon in Columbia County, which is located between Jacksonville and Tallahassee, Sheriff Mark Hunter told WJAX. There were no homicides there last year.
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