While I can't speak for other countries and how they handle procedures upon receiving an emergency call, in America, when someone dials 9-1-1 and then hangs up, a police officer will immediately be dispatched to the geolocation that the phone used to call the Emergency line was received from.
It's a failsafe that's worked out between emergency services and phone companies. Since cell phones had yet to become commonplace in 1998, meaning Landlines were a thing, it was incredibly simple to retrieve our address and send a police presence to the house.
Not only that but by giving the minor amounts of details that I had, such as mommy and daddy fighting and blood, along with it being nighttime, not one but two police cars would be sent along with an ambulance.
