Landlords responsibility towards neighboring homeowners?

I own my own home and the neighbor is a rental property. He is currently renting to a family with 2 kids, mother and boyfriend and their 4 dogs. This neighbor’s 4 dogs bark nonstop when we are in our own yard and if we ask them to quiet their dog they get verbally abusive. However they will make barking noises (the kids) when we have our dog in our own yard to get her to bark and then they yell to quiet the dog down or else. They have thrown things over our fence into our yard and if we ask them to be careful they start cursing and threatening us with violence. We have contacted the local police department about this issue and they advise us to contact the landlord. We have but he does nothing. The situation is getting worse and summer is coming up. Can anyone give us advice on how to stop this before it gets worse? We live in Pennsylvania and need advice.