is, report this to the police instead. Don't get directly involved with him. If he isn't than I would be direct with him like others have said. Not accusatory, but direct in seeking understanding what he is doing. If he is a member of your ward (assuming you are a member of the COJCOLDS), and it is an issue, talk with your Bishop so he can maybe set up an interview with this guy and hopefully cut of at the pass any potential for going down a dark path.