Here's a pic of my JRT
In a way I'm not real surprised that it took on a few pit bulls. The JRT was originally bred with the stamina to run with a pack of horses and the tenacity to take on foxes and Badgers at the same time, and seem to have it hard wired into their brain that they don't give up in a fight. I've seen mine on many occasion go after dogs up to 4 times his size if they're not submissive enough for his liking, and if not for quick intervention would probably end up on the short end of a dog fight.
Still, it's sad to see that there's still bangers in the world that have pit bulls (or any other agressive breed) and don't train them properly.