It seems like a good thing to search all the people with a similar briefcase in the area.
This will directly help to resolve the case and reassure the population that the police takes the situation very seriously.
A geofence fails that criteria because it doesn't say who is to be searched, it also has an overly broad place.
An address explicitly listing buildings is half of appropriate criteria, a city block is not. A 2 mile radius is not.
The other half is the specific people or items.