Same deal. Claiming to be from cra. I did call back out of curiosity and "officer " Thomas Scott (who has a thick Indian accent so not likely his real name) informed me that cra did an audit on my 2010-2014 taxes and they believe I willingly claimed things and purposefully defrauded them via taxes. So. I called the company that does my taxes. They said they've received lots of calls like mine and it is indeed a scam. Not sure how this scam is supposed to play out since the conversation ended with him saying... "ok, I guess you can just wait for the police to show up at your door." I meant to ask for his badge number but forgot. Ok tough guy. I'm soooo scared.
I got the same call this morning. If he doesn't hear from me right away, he wishes Good Luck Lol!.
He claims to be calling from CRA. Hence Carribean/Indian acccess.
Adding to my post above, the carrier is a company called Iristel which operates an international switching gateway, according to a Wikipedia article about them. I suspect when you call back you may be incurring international call rates.