I'm guessing he was referring to the Macedonian teenagers from https://www.buzzfeed.com/craigsilverman/how-macedonia-became...
This tiny little episode shows how easy it can be for wrong info to spread. I should have looked up the Buzzfeed story to confirm the country, but I winged it, and got it wrong.
So was my comment "fake news"? I don't think so, of course. I didn't set out to fool anybody, it was just a mistake. But it did push out a false fact to everyone who saw my comment.