The University of Oklahoma said late on Friday that its Norman campus was safe and no threat had been found after police investigated a suspected shooting on the premises.
University officials said on social media a comprehensive search had been conducted and no danger was detected and authorities issued an "all clear" notification.
"There is no threat to campus. Alert has been canceled," the university said on Twitter.
Earlier on Friday, the school implemented a shelter-in-place protocol after a report of an active shooter at the Van Fleet Oval, a central location on the campus.