Call the police and explain the dog has already attacked your dog and presents a threat to you and your family. They will send an officer. I recently went through something similar and the owner of the attacking dog was court mandated to keep the dog on a leash at all times while in public. She refused, I called again and the dog was removed from her ownership. It’s important to remember that the animal may not be to blame in this situation. I was raised training and hunting with dogs and my father also said “There’s no such thing ad a bad dog. Just bad training.”