If you are in immediate danger call 999 and ask for the police. If you are in danger and unable to talk on the phone, call 999 and listen to the questions from the operator and if possible, respond by coughing or tapping the head set. If prompted, press 55 to Make Yourself Heard and this will transfer your call to the police. (NB Pressing 55 only works on mobiles and does not allow police to track your location.)
When 999 calls are made from landlines, information about your location should be automatically available to the call handlers to help provide a response.