Henry Horton IV, South Florida man arrested with plans to kill everyone at former high school in mass shooting along with stabbing attack at Miami church. Had recently sought mental health treatment for recurring thoughts.
Would he have gone through with it? Authorities in South Florida arrested a 19-year-old after coming across written threats for a shooting spree and other attacks in his vehicle during a routine traffic stop. The plans detailed plans purchase firearms and to to ‘kill everyone’ at his former high school and others across multiple states on his 22nd birthday.
Henry Joseph Horton IV, 19, of Okeechobee was pulled over in Jupiter on Sept. 27 for a broken headlight when a search of the vehicle uncovered the alleged manifesto plans, WBPF reported.
One of the notes read, ‘kill everyone at OHS with my guns.’ Horton allegedly confessed that it referred to Okeechobee High School, where he graduated in May 2022, according to a probable cause affidavit.
Recurring thoughts and history of mental health issues
Police said the notes outlined a plan for Horton to kill an administrator at the school, along with 14 others on the campus on January 2, 2026, on his 22nd birthday.
An investigation into his phone and Discord account also uncovered details for mass murder attacks in multiple states, plans to build a bomb, and plans to kill his stepmother.
During an interview with Horton, the suspect told police he was in Palm Beach County to do reconnaissance on the El Rey Jesus Church, in Miami, as part of a stabbing attack he was planning there, according to the Palm Beach County Sheriff’s Office.
Horton also claimed to have done recon work at the Marjory Stoneman Douglas High School, where 17 people were killed during a mass shooting in 2018. Police said his car was seen in Parkland on Sept. 11.
Along with his notes, police also seized a 9MM handgun Horton said he stole from his mother.
Horton said while living in Virginia, he voluntarily admitted himself to a medical facility for a mental health evaluation due to thoughts involving mass murder, the affidavit stated.
Horton, who has a history of mental health problems, was transported to a hospital under Florida’s Baker Act, where he remained committed until he was arrested on Thursday.
The teen’s father regaled against the alleged murder plots, insisting that Horton isn’t dangerous and that the notes were a ‘cry for help.’
Cry for help
The father speaking to WPTV said the son confided in him saying that he ‘had these thoughts’ without clarifying the nature of the thoughts and that he couldn’t control them and that they kept recurring.
The suspect’s father said his son had checked himself into a mental institution and was sent to be with his mom in Okeechobee County to continue treatment.
His mother, Marcie Horton, said she couldn’t excuse her son’s actions but asked officials to allow him to receive the mental health treatment he needs rather than face charges over the plans.
She told WPF that her son was a ‘good kid’ and would never have actually carried out the plan.
‘It’s no excuse for what he wrote,’ she said. ‘I’m not saying that, but he needs help.’
Stepmother, Alisha Horton, who was included as a would-be victim in Horton’s plans, reiterated her stepson’s innocence.
‘Henry isn’t going to hurt me,’ she told WBF. ‘He would never… He needs to be treated for a mental disability instead of as a criminal.’
Horton was charged with intimidation with written threats to kill or harm another individual.
He was booked at the Palm Beach County Jail and remains held on a $1 million bond. He is scheduled to appear in court on Nov. 6.
