I'd say it's lying since it's about implying something that isn't true.
Not so sure and it is for precisely the reasons I have said. He has not tied himself down to anything. It may well be something specific that he is alluding to is an oblique way. Maybe it is the riots specifically and maybe more specific information as to why the riots here, in particular, are of special interest. You tell us it is a mundane seasonal thing. That is not something I care to question BUT what IF these riots, in particular, THIS time were fueled or organised by something other than they have in past years and it is indicative of a larger issue that he was aware of.
Something like that would make sense. But was it about the riots at all, even? That again is the problem. We could do a big back and forth and look at that premise from all sides and see whether he was right in what he said on the basis that the riots were his reasoning for saying what he said and at the end of it, it possibly was not even what he was alluding to.
I do not know what he was saying and so whether or not he was lying. Nor do you. Nor does anyone here. In fact none of even know what he was alluding to.
As for whether this is fear-mongering? I don't know. I do not think that vague assertions really stoke fear.
"Russians are getting pretty edgy and hinting at possible military action" or "Russians are going to drop a nuke on us if we do not pull troops back from the Russian border"
One would stoke concern and interest the other would stoke fear and panic and a demand for things to be done asap.
So fear mongering? Maybe? I don't know.