A Skyridge High School student has been arrested after he told a therapist he wanted to “shoot up his school.”

The 18-year-old from Lehi told the therapist “he has a detailed plan to murder someone ... that molested or raped his friend,” and that “he has a fascination and obsession with death,” according to a probable cause statement.

The therapist, who works at Solace Emotional Health in Pleasant Grove, notified police of the threat. The suspect did not disclose who he was targeting or when he planned to carry out the attack, “he only explained that he fantasizes over these murderous thoughts constantly” and spent more than three hours on Wednesday night “planning it out,” the document said.

The therapist and the owner of the facility told police the teenager “sees himself as a vigilante and claimed he wants to harm those that hurt others.”

Police went to Skyridge High and searched for the suspect, but did not find him. After pinging his cell phone, he was located at his home and arrested on Wednesday evening. After being advised of his rights, the teenager “opened up, releasing frustration, odd responses, and several bone-chilling responses to our questions,” according to police.

“After speaking with [him], all officers on scene felt the next step of [his] plan” was carrying out an attack “on Skyridge High School and specific people,” the statement said.

The teenager was booked into the Utah County Jail for investigation of making a threat of terrorism, a second-degree felony.

Skyridge Principal Joel Perkins emailed parents that police had “determined there was no additional threat. Our students, faculty, and staff are all safe.”