Distressed animal next door

Its almost 1 in the morning and all I can hear is one of my neighbors dogs literally wailing and shrieking for the last hour.. To the point where I went for a walk to see if it was being abused! I normally mind my own business but its terrible sounding so I called bylaw. The operator could even hear the dog through my phone. I was told the only way to get something done about it tonight would be to call the police, which I'm unsure about. Advice???