Sam Barlow High School in Gresham was temporarily put on lockdown while authorities investigated a possible weapon on or near the campus, a report which turned out to be false.
The Gresham-Barlow School District posted an update on social media around 11:40 a.m. stating that the school building was locked and students were remaining in their classrooms.
They also noted that no one was allowed out of the building nor were school officials letting anyone inside.
According to the Multnomah County Sheriff's Office, deputies responded to the high school just before 11 a.m.
The lockdown was prompted by a student at the school who reported seeing another student on campus with a handgun Thursday morning. Deputies searched the school and found no shots had been fired.
The Gresham Police Department reported that there nearly two dozen uniformed officers from their department and the Multnomah County Sheriff's Office reported to the scene.
About an hour and a half after the lockdown was announced, it was lifted.
The sheriff's office said one person had been detained and was being interviewed.
Following the interview and investigation, the sheriff's office determined the 911 call about a student with a gun was a hoax.
Deputies said detectives will take the information for a follow up investigation.
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