abusive children

Two of our neighborhood kids killed a neighbor's cat. They were teasing it. Some adults saw it and told them to stop. Later, according to some other neighborhood kids, they ran over it several times with a bicycle. Another neighbor found it dead under her bushes. The cat's human went to talk to the parents about what the children did. Of course, they were in complete denial. They said that the girls who witnessed the boys killing the cat were lying. They blamed the death on another neighbor. They said that three of their own cats had been poisoned (hhhmmmmm...) and they believed that a neighbor did it.

The cat's human called the police because the parents wouldn't do anything. They said that they couldn't do it because the girls weren't reliable witnesses. Several neighbors are very upset about this incident. While I am upset about what they did to the cat, I am VERY concerned about the violence displayed by these children. I know that cruelty to animals can become more frequent and may even extend to violence toward humans. I really think that the kids need some serious counseling. Do you have any suggestions for what we can do to address this issue?