Just my 2 cents:

If I were the mayor of that city I would ask all residents to be vigilant and watch any younger stranger and also (being from Texas) I would ask all residents who own firearms and are properly trained (ex-military etc) to carry concealed firearms and to be prepared to take down a shooter.

STM

See this has to be a false flag, because a real Islamic terrorist would never be able to get away. They are just too stupid to think such things. Any terrorist attack committed by Muslims is always one way ticket to paradise. A real Muslim would never try to escape from paradise.

Well, the talk out there is that Delhi is next. I would not doubt that there were more than 10 to start with just from how long it took to quell the thing in the first place and how widespread the shooting was.
If any escaped they are probably in Delhi now, or on their way, for the second stage.
Nothing I have said is to take away the possibility that the whole thing was set up as a false flag. There is no mistaking the fact that Pakistan is in everyone's cross-hairs right now, in terms stirring up as much negative news as possible.