This is how The Star frames it.
"The chain of events began two years ago, sparked by local teenagers roving through Internet sites, reading and espousing anti-Western sentiments and vowing to attack at home, in the name of oppressed Muslims here and abroad.
Their words were sometimes encrypted, the Internet sites where they communicated allegedly restricted by passwords, but Canadian spies back in 2004 were reading them." (emphasis mine)
And presumably all along since then.
As well as this, right now.