Florida Boy, 9, Allegedly Stabs Sister, 5, in What Police Call a 'Really Disturbing Scene'

Police arrested a 9-year-old boy who was allegedly seen repeatedly stabbing his younger sister.

On Monday, an Ocala, Florida, mom left her two children playing together when she went to pick up the mail, according to a probable cause affidavit obtained by PEOPLE. When she returned after 10 minutes, she said she witnessed her son stabbing his 5-year-old sister in the back, shouting, “Die, die.”

Shortly before 5 p.m. on Monday, the Ocala Police Department shared an update on Facebook, saying the boy was in custody as the girl was taken to a nearby hospital.

According to the affidavit, the mother grabbed the large kitchen knife from her son, who then ran outside as she checked on her daughter and called 911. The boy was found near the apartment complex, hiding in a maintenance shed.

The Associated Press reported that the girl was “alert and responsive” when she was air-lifted to the hospital.

“It was just a really disturbing scene,” an Ocala Police spokesperson told WOFL.

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According to the affidavit, the boy is charged with attempted first-degree murder, and allegedly told detectives that he stabbed his sister because he “wanted to be able to go outside” — and that he first got the idea of killing her two days before the incident.

“This is a heartbreaking case,” Ocala Police spokesperson Corie Byrd told PEOPLE in a statement. “The Ocala Police Department wishes for the speedy recovery of the victim and appropriate action from the state for the suspect; whether that be detention or assistance, the end goal is for both of these children to be able to return to normal functioning lives within the community.”

On Tuesday, a judge ordered that the boy receive a psychiatric evaluation, according to WOFL, and his next court appearance is on Wednesday, Feb. 5.

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A spokesperson for the Ocala Police Department told WOFL that they expect to see “lasting impact” on the community in the wake of the incident.

“I think the best case scenario here is to get this young man some help,” the spokesperson told the outlet. “A lot of people were affected by this, so we’re going to see the lasting impact here in this community.”

According to WKMG, the boy — who is not identified by because of his age — was appointed a public defender and remains in custody.

Police said the girl is in “stable” condition after suffering the multiple stab wounds.