Sister-in-law walked her dog to the dog park daily. It had played several times with a particular pit bull with no issues. But one day that pit bull tore her dog up. Her dog survived a year or so after an expensive vet visit. Gone now.
A couple months ago, my friend's wife was visiting her parents. Sitting outside, they heard horrific dog sounds, and went to investigate. A large dog was calmly holding a small beagle in its jaws. She managed to wrestle the small dog away from the big dog, but suffered some deep bites to her forearm for her efforts. The smaller dog had lost a lot of blood.
She called the dog owners repeatedly over the next month, trying to find out what happened. The owners ignored her calls for the longest time. She finally heard the small dog had died. No word on any consequences for the large dog, and no offers to help pay any medical bills incurred by my friend's wife.