Last updated at 4:35 p.m.
The University of Oregon said "normal activities" can resume after an earlier bomb threat caused an evacuation of Hayward Field.
The university first issued an alert just after 1:30 p.m. Tuesday and said University of Oregon police and "partner agencies" were on the scene investigating.
Around 4 p.m., the UO issued an "all clear" and said "a search turned up nothing of concern."
The venue is preparing to host the NCAA Track and Field championships starting Wednesday. The evacuation disrupted athletes who were preparing for the event, forcing them to seek other venues to practice on Tuesday.
An update emailed to news organizations from the NCAA said despite the "all clear," Hayward would remain closed for practice for the rest of Tuesday.