TROY, Ill. (AP) – A Metro-East high school was locked down for about three hours when two bullets were found.

The Belleville News-Democrat reports that a teacher found the first round of ammunition Monday morning in a stairwell at Triad High School in Troy. That prompted the lock down. The Madison County Sheriff’s Department sent a dozen officers to respond. An officer found a second bullet in a different location at the school.

Officers searched the school, lockers, student backpacks and students’ pockets. Triad Community School Unit District 2 Superintendent Leigh Lewis says authorities didn’t find any other items that would jeopardize student safety. The lockdown was lifted at 10:40 a.m.

Students were kept in their classrooms during the lockdown.

Troy is about 20 miles east of St. Louis.

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