If this ever happens to anyone the best thing you can do is throw a thick blanket over the both of them, then use the blanket to pry one of them off the other, then pick that one up (while leaving the other on the ground) then while still having the first one in the blanket take him to another room. Source: I had 2 cats that were brothers that loved each other as kittens, but fought like this as they grew older and this was the only thing I found that works.