Trinity High School remained closed all day Friday after a student discovered on Thursday a threatening note scribbled across the back of a chair in chemistry class. It warned that a shooting would take place the next day during fourth period. School officials and police officers investigated late into the night and throughout much of the next day, including interviews with students and bomb-sniffing dogs. Trinity president Rob Mullen says he erred on the side of caution, and now school has re-opened.“We’re now confident that the campus is safe, and it’s reopened. From every angle, based upon what we have found over the past 24 hours, as well from the police investigation, the note scrawled on the desk does not appear to be a credible threat," says Mullen.Mullen says the investigation will continue with more student interviews. He didn’t specify what consequences the responsible party might face if caught.