How to report someone to Social Services?

Okay.. I know a family that has custody at the moment of 3 children. I know for a fact that there is a lot wrong in the home..favortisim, drugs, loaded guns in childs reach, and improper living... they we're awarded custody while they we're living in another home and since SS has backed off they have moved this family of 6 in to a 2 bedroom duplex. This is in North Carolina and I would like to do this with out leaving my name or my information.. These children are 5,4, and 3.. and I want what is best for them.. I think that SS messed up by letting them foster these children.