Unfortunately, I can't give you a specific case for Canada, but I will give you a specific case for the United States, which I believe kind of transcends throughout North America.
Venezuela has essentially an agreement with Iran that allows for certain flights to travel to and from Caracas and Tehran that have no oversight. There's no way to look at the manifest of who comes in and out of those flights. Essentially, we have seen through other intelligence sharing and information collection that some of these individuals who came from these flights then changed their identities, were given Venezuelan passports with Venezuelan identities, and then had been pushed on to Latin America.
In one case, a gentleman named Kareem Ibrahim attempted to put a sort of pipe bomb at JFK International Airport in 2006. He was arrested in Trinidad and Tobago on his way back to Iran via Venezuela, via that flight. Thankfully our law enforcement captured that individual.
So that was one incident where basically a falsified passport allowed someone entry into the United States, and thankfully our law enforcement caught it.