Plane Diverts from Toronto

An El Al flight bound for Toronto and Los Angeles was diverted to Montreal and later to Hamilton (less than an hour away from Toronto). It was also diverted on the way back from LA. A well known rabbi was on that flight and spoke about it in shul (synagogue) today. He said that when the flight was grounded in Montreal, the plane was under heavy guard. There was also a helicopter circling above, which he joked was the army's only helicopter. Apparently, there was an unconfirmed threat that terrorists were planning on downing the aircraft with a surface-to-air missile. This has been attempted before in Africa on another Israeli airline. My only question is, wouldn't it be somewhat difficult to obtain a missile here in Canada? I can understand being able to procure such a weapon in Africa. But, I wonder how it would be possible to get such a thing here in Toronto? Perhaps the security officials were being overly cautious (better safe than sorry). I hope we'll find out more on this story soon.