What can i do about my neighbor's dogs?

There's 4 of them, 2 golden retreivers and 2 lapso apso. They're always barking and constantly get loose. Me and 2 of my other neighbors have tried to talk to them about their dags before but they do nothing. When one of their dogs get loose they don't go after them until someone yells at them to get their dog. The dogs aren't nice and have killed a stray kitten and knocked a little boy off his bike before. The owners are very rude and won't do anything. Their yard is also extremely messy. We have tried calling the dog warden and police but they do nothing. Is there anything else I can do to get them to control their dogs?