Authorities said while the horse was loose, it hit a 13-year old girl causing minor injuries, and she was taken to a hospital, as reported by the O.C. Register.
Disneyland has their own ranch, called Circle D, as we reported in this post. They train their horses there and keep them in barns. They also train dogs there including dogs that can sniff out drugs, bombs and bed bugs.
Usually Disneyland will give a child who gets hurt onsite a stuffed Mickey Mouse doll but the little girl who was hurt by the runaway horse has a good lawsuit on her hands, if her parents decide to lawyer up.