Map the people involved in the victim party.
Find out where they lived before the incident and then find out where they lived after the incident.
You should also take a look at the local PD.

I saw a video of sandy hook. A guy in camo running through the woods near the school A newsman in a helicopter got the aerial shot. A police dog ran him down, followed closely by police. The news org mentioned a man in custody but nothing came of it. Are we meant to believe it was just some dude jogging through the trees, dressed up in playful clothes?