A Smithfield High School student who left the building and then later re-entered set off an alarm and triggered a lockdown Tuesday that lasted for more than an hour.
School officials said a student left the building at about 12:45 p.m. through a side door. The student tried to come back in, but the door was locked.
Another student opened the door, which set off the alarm.
A staff member heard the alarm go off and saw the student enter the building with a backpack. The staff member reported it to the main office, and the high school immediately went into lockdown.
"An officer came in with guns drawn and I thought, 'Oh my God this is real.' We were worried didn't know what to do so we just sat there," said student Kedreack Brown.
"A girl in my class started crying. It was freaky. We had no idea what was going on," said student Gianna Goneconte.
Police arrived at the school in moments, and conducted a room-to-room search.
Parents were anxious not knowing what was going on.
"There were police officers with assault rifles asking if students were hurt, not hurt. My daughter texted me very scared. She said, 'Please stay on the phone with me,'" said parent Shanyn Turner.
An alert was sent from the school to parents explaining what had triggered the lockdown.
The lockdown was lifted at about 2:15 p.m., and the school started dismissing students.
School officials said everyone at the school did the right thing and that their emergency response plan was implemented exactly how it should have been had it been a real threat.