999
The service was introduced following a house fire in which 5 people were killed, when a call to the fire brigade was held up at the local telephone exchange. It is the world's oldest emergency call telephone service. 999 is still the official emergency number for the United Kingdom in the 21st century, although calls are also accepted on the European Union emergency number, 112. Countries and territories also using 999 as the emergency number during the 21st century include Bahrain, Bangladesh, Botswana, Eswatini, Ghana, Hong Kong, Ireland, the Isle of Man, Kenya, Macau, Malaysia, Mauritius, Poland, Qatar, Sudan, Saudi Arabia, Singapore, Trinidad and Tobago, the Seychelles, Uganda, the United Arab Emirates, and Zimbabwe.