What platform? It may be a known glitch (like REPCONN on the Xbox), or possibly a hardware problem where your video card can't render everything it needs to (on the PC).
Its a ps3. I just checked the disk for scratches and there was a minor one on the outer part of the disk. Would that scratch cause the game to freeze.
Maybe, although my guess is that it is a glitch that is unfixed. it might get fixed. sorry bro happens to me lots as well.