Honestly I think I would go one step further and contact the police. You never know if he's been building up his nerve to actually accost someone... So maybe other people in the area have reported similar run ins. Either way you might be surprised at how far the police will go and it might deter him from doing this sort of thing again if they look up his info and pay him a visit. I watched a mother jerk her little three year old around a store once so roughly I literally waited for them to leave to get her car information. It bothered me that she was willing to do that in public what would she do behind closed doors. I did report it and apparently they did pay her a visit. At least the police could tell you if the guy has a record or something to that effect so you know whether or not this is a real nutcase or if he was just having a bad day and taking it out on you. It would certainly put me at ease on the next long run. Perhaps the police can also offer you suggestions on what to do if it happens again.