Police said the 14-year-old Florida boy told them he’d been upset about getting grounded for bad grades, that he had “built up anger” toward his family members and that he wanted them killed.

So he wrote up what reads like a murder-for-hire contract and offered a friend $1,200 to kill his father, stepmother and stepbrother, police in Port St. Lucie said. His father discovered the note in the boy’s bedroom.

Police arrested the boy Sunday and charged him with attempting to solicit murder. He’s being held at a juvenile detention center.

The Washington Post generally does not name juveniles accused of crimes unless they are charged as adults. Prosecutors have not yet decided whether to try the boy as an adult, Port St. Lucie police spokesman Frank Sabol told The Post.

According to the affidavit, the boy told detectives that he’d been depressed and angry about getting grounded for poor grades. He told police that he’d written the contract within a few weeks of school starting, and that his friend, thinking it was a joke, signed the contract a few weeks ago.

The boy’s plan was to stage a burglary-gone-wrong, according to the affidavit: His friend would come over and, with the boy in the room, shoot the father, stepmother and stepbrother. The boy would then go to a neighbor’s house and call 911 to report the break-in.

The note read: “I [name redacted] will be hitman for hire for [name redacted] to murder [names redacted]. I am aware that if I do not go through with it I will not get paid. Money in question we agreed upon was 1200 dollars. I will leave in an hour or two within the murder.”

The friend told detectives that he was working on a school project when he was approached by the suspect. He didn’t think the contract was legitimate, so he signed it and didn’t think about it again, he told police. “We interviewed him and he’s a good kid, he’s just being bothered by this guy,” said Sabol, the police spokesman.

According to the affidavit, the 14-year-old boy said he had previously thought about killing his parents but didn’t know how to go about it.

Port St. Lucie was home to an infamous case of parricide in 2011, when teenager Tyler Hadley killed his parents with a hammer and then threw a house party while the bodies were still inside. A judge found Hadley, who was 17 at the time of the crime, guilty of first-degree murder and in 2014 sentenced him to life in prison without parole.

“We have to take things like this seriously, because you have the intimacy of family,” Sabol said. “They have total access to each other and you want to make sure if something like this comes to light, we want to make sure it doesn’t occur and that you take appropriate action.”

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