It is not particularly uncommon for a student to be caught with some kind of weapon on Chicago Public School property and lockdowns do occur.
But in this case the I-Team has learned that it was at an elementary school, Mary Gage Peterson School on the North Side.
We heard about the incident that triggered this school lockdown last week, shortly after it occurred, but authorities were not quick to respond to questions about what happened.
School officials, Chicago police, parents and concerned neighbors have now provided a more complete picture of what happened here at the Peterson Elementary School on Wednesday of last week.
Investigators say a 13-year-old boy arrived at school carrying several rounds of live ammo, various calibers, possibly as many as 50 rounds, according to one source.
The boy was also carrying a clip to a handgun that also contained bullets.
According to a letter from the principal that later went out to parents, "Authorities were notified and took immediate action. As a precaution, the school was placed on lock down for approximately one hour. The entire building and property were methodically searched and no other objects were found."
That day emergency robocalls also went out to students' families according to school officials.
Chicago police said that the 13-year-old has been arrested and charged with four juvenile misdemeanors: Possession of ammunition, reckless conduct and two counts of aggravated assault on public property.
According to the CPS student code of conduct, bringing ammunition to school is no different than having an actual gun and the principal must refer the student for expulsion. He also vowed a commitment to addressing those whose "silence is complicit in endangering our children." In other words, those who see but do not say.