Thats just a bad attempt at face-saving from Russia. What else can they say? That Ukrainians blew it up and we with all our fancy tech were caught sleeping? Obviously admitting to that would be utter humiliation so rather make up some story about a truck and terrorists lol.this looks really bad for Russian internal security. They cannot ID someone driving a truck loaded with explosives onto supposedly the most critical and secured bridge in Russia? There's no checkpoints or scanners?
What is pretty clear is that NATO is too much for Russia to handle alone.