And as police begin to piece together a picture of the gunman, Adam Lanza, they will also be looking at possible motives. Here in the studio with me is NPR science correspondent Shankar Vedantam.
And, Shankar, you have reported in the past about building profiles of these kinds of assailants. I mean, usually, we're talking about men. We're talking about often about white men. Does what we know about Lanza fit that profile of a mass shooter?
It's WEEKENDS on ALL THINGS CONSIDERED from NPR News. I'm Guy Raz. Fred Rogers, better known as Mr. Rogers, was often asked by parents how to explain death to children. And so on his program one day, he decided to try and deal with that challenge. And here's how he started:
FRED ROGERS: When I was very young, I had a dog that I loved very much. Her name was Mitzi. And she got to be old, and she died. I was very sad when she died, because she and I were good pals. And when she died, I cried.