K.
If it happens again,I would simply call the police out. The people above don't have to know you are the one that called. I would look at it like this. Your children come before anything and you are right to be concerned. I would not allow it to go on. If they are using and or selling drugs that is going to create a dangerous environment for both you and your children. People on drugs can do all sorts of things that they might not normally do, and if they are also selling them then that brings all kinds of drug addicts into your home area! Good for you that you are thinking of your children. Best of Luck!
K.