If you believe an agency is investigating you for a potential crime it is imperative that you hire a lawyer to represent you and protect your rights and interests. Never wait to see what happens, and do not think that you can resolve the issue yourself.
If a government agency contacts you and asks you to come in and speak with them refer them to your lawyer. Do not talk to the police. You have a constitutional right to remain silent and this is the time you must use it. Government agencies investigate people for a whole host of crimes ranging from white collar crimes, such as money laundering, burglary, lewd acts with children and sex offenses, arson, terrorism and murder. No charge is more important than another when your liberty is at stake, and all must be handled by a professional who can navigate the system for you.
I have worked with clients in this situation numerous times and have had success in ensuring that no charges are filed against my clients. Let me do the same for you!