Police said they arrested Nicholas Graham after he allegedly made threats after getting into an argument on the social media platform, and that he would "find them and kill them, and all of their friends".
The threat led to several calls to police from parents.
Police said that Graham told them he didn't have any intention of hurting anyone, and that his posts were motivated by emotion and anger. Police said he was taken to St. Vincent's Medical Center, evaluated, and remained in police custody.
Graham was charged with breach of peace, threatening, and harassment. He was in court on Wednesday.
Police said at this time, there is no indication that Graham has the capacity to carry out the threats, but there was an increase in police at the schools on Wednesday.
Police commend the public for coming forward and reporting what they see as potential risks to schools and students.