TULSA - The high school in Cleveland, Oklahoma was locked down about 10:30 Wednesday morning after a threat involving a gun was posted on a social media app.
"Yik Yak" allows anonymous posts which are seen by other people who log in from the same geographical area.
Educators say "Yik Yak" has increasingly been used for online bullying, but in this case it was used to issue a threat.
Cleveland police responded to the school to conduct a search of lockers and backpacks to ensure that no gun was actually present.
As of noon the search continued, but nothing had turned up in the form of a weapon.
A school employee, who wished to remain anonymous, told KRMG there was no evacuation, but that the school would remain under a lockdown until police and administrators were satisfied that everyone was safe.