[DoughtyOne]

It might be best to take the name and addresses of every person inside those paremeters. Then cross reference the next time. Within a few times, you might begin to see some repeats. They could be checked out extensively.

[Steve0113]

The problem with that is that over a hundred thousand cars cross that bridge every day.

[The Red Zone]

I'd be interested in commonalities between businesses, homes, etc. that could serve as safe houses. The sniper is probably getting away on foot, not by vehicle.