Where do I go to, to report dog owners

There's a family in the locality with some dogs. These dogs are mongrels. I think they are tied up in sheds more often than not but I can't be sure about where the dogs are housed. If my suspicions are right, and they are locked up all day, they are building up a lot of energy. These dogs get loose and run around on the road. They used to come out in a pack of three but now there's only two of them. When I am out walking and if the dogs are out, they circle me, around and around with their mouths wide open and their tongues hanging out. I find them intimating. I am probably not the only person experiencing this. I think it's only a matter of time before these dogs will hurt someone and cause damage to someone. I usually like dogs and I get on well with many dogs but I don't like these ones.

Where do I go to report the dog owners? What is usually done with this? I think the dogs should at least be muzzled when they are out roaming on the roads.