The RCMP is famous for its stings. My bet is that CSIS found these guys on the internet, and from the local muslims who got bumped out of their mosque when they took it over. Not everybody (or even most people) were ready for, or interested in the wahabbist power hour they set up.
After that it would have gone to RCMP, who would have controlled the availability of the bomb materials to them, gathered up evidence of intent, and figured out who was who in the organization. After enough gathering, they opened the trap door, and here we are.
Lots of our domestic terrorists find that "Mother Mountie" is a very generous old bird when it comes to useful terror toys. Unfortunately she isn't really to be trusted, and has some very hard men at her disposal. This is an old game, and it just got a few more losers.
Our hats are off in respect for the RCMP. The law enforcement types in this country could probably learn from them.
Good Hunting!!!