National School Safety and Security Services receives a number of inquiries about metal detectors and school safety, especially after high-profile school shootings or other incidents of school violence involving weapons. Frederick County Public School Communications Director Michael Doerrer says although local schools do not have metal detectors, it has been a topic of discussion. "It's a balance when we're thinking about how best to prepare for emergencies of any kind. What are appropriate steps we can take to reasonably assure that our buildings are safe? I'm confident that we are doing everything we can right now to prepare for emergencies of all kinds, " said Doerrer.

He says no one can just walk into a Frederick County Public School. Employees have to use a card key to enter and visitors have to be screened and buzzed in at the front door. Connecticut State Police say the gunman who massacred 26 children and adults at an elementary school before committing suicide forced his way into the building. Lt. Paul Vance said Saturday morning that the suspect was not voluntarily let into Sandy Hook Elementary School in Newtown.

Authorities say 20-year-old Adam Lanza shot his mother on Friday, drove her car to Sandy Hook Elementary School in Newtown, and shot 20 children, six adults and himself.