Well, no one is going to say that the dog actually called the emergency number through the phone by intention, but it happened that way. It seems very weird when you read the news, but the actual fact is that the dog somehow got his neck entangled in the long wire of the landline telephone, and through the twisting while trying to get away from the wire, managed to press the emergency number (999) which is the emergency number of the United Kingdom.
This managed to get the emergency services to the home, but they were looking for some human who was injured or in an emergency condition, but it was a neighbor who came to the house and who managed to detect the dog in a choking condition and helped the dog get away from the wire (link to article):
The operator at the other end could only hear heavy breathing and gasping. Sensing an emergency situation, the operator alerted the police, who rushed to the empty home of driving instructor Steve Brown and daughter Lydia. The police team began searching for an aged or injured person in the house, located in South Hiendley, West Yorkshire.
It was only when a neighbour, Paul Walker, walked into the living room that George was found choking — with the phone wound tightly round his neck.