Can you deny there were no local elements involved? I doubt if a large scale incident can be executed without involvement of local elements. There should atleast be a dozen odd members if not more.
What is shocking is that the community around them is unable to deteect these planning, execution (like procurement, bomb making, placing of it at various places, etc). They need money, logistic support, food, material access etc.
The sad part is those who are REALLY against such elements too will be painted by the brush of doubt (if not, hate).
Our government policies favor the criminal than the law abiding citizen. We are fed up of the sweet nothings uttered by these politicians.