ST. CHARLES – In response to a bullet found Thursday in St. Charles North High School, the backpacks students toted that day are under lock and key in various classrooms as administrators scan each one with an X-ray wand, St. Charles School District 303 Superintendent Don Schlomann said.

The Bureau of Alcohol, Tobacco, Firearms and Explosives is also involved and was expected to bring K-9 dogs to help search for live ammunition and weapons, he said.

Any backpack warranting further inspection will be opened by its owner in front of an administrator when school resumes Friday, he said.