Schools eye plans, calm parents after Conn. attack

(AP) — The mass killing inside a Connecticut elementary school has educators across the country reviewing their security measures and reassuring parents through text messages, emails and phone calls that their buildings are safe.

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Driven by previous school shootings, many district officials say they already lock building doors, require identification from visitors, employ safety officers and have systems to notify parents of trouble..

Photos: Newtown school shooting

Some rely on metal detectors and cameras.

But for all the preparation, experts say there are no guarantees.

The heightened vigilance was evident Friday when a New York City school was locked down after students reported seeing a man they didn't recognize. He was servicing the copy machine.