What would you do....?

There has been this really creepy guy hanging out in my neighborhood for almost a week now. He just appeared out of nowhere. He seems to be homeless, but that is not the problem. There are other homeless people that hang out by the train tracks across the street that never bother us. The first time we saw him, he was about two hundred yards away just hooting and hollering to himself, and he was sitting dangerously close to the tracks when a train came by. The other day my husband heard him in the distance singing about killing people! He made no direct threats and was still a fair distance from our house, but he was saying some very disturbing things. Everybody says we should call the cops, but we're not sure if there is anything they will actually be able to do about it. Has he actually broken any laws? The jails in our area are pretty crowded, and the don't have the room to lock people up for minor offenses. What if it just makes this crazy guy angry that we called the cops? My husband did confront him last night; he made it clear that we don't want the guy around here. He has kept his distance, but we've seen him across the road a few times again today. What would you do?