<< If I go to a website that accuse the US of being the devil and Israel the little devil, and all Americans should be killed, should I believe it too? I'm sure such a website would provide "concrete evidence" to support such a claim. >>
You see this sort of thing everyday (to a varying degree), it's called the media. If the media tells me lots of carrots are good, do I take that for a fact?
As for "concrete evidence", he's basically got that. He's putting it out there and you're welcome to refute his pictures. Heck, get in touch with him and talk to the policefolk he's worked with if you're that bugged by the "possible" chance that he's making baseless accusations.