DENVER | Police in Denver are investigating after a student brought ammunition to school.

Officer Vina Maciel said the ammunition was found in the student’s pocket at Hill Middle School on Monday, prompting a lockdown. She declined to say what type it was as police investigate what happened.

Police searched the building but didn’t find any weapon.

School officials said all students and teachers were safe and the tightened security was lifted.

The discovery follows security concerns that disrupted schools in the Denver area in the days leading up to the 20th anniversary of the Columbine school shooting.

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