Criminal Law Questions? Ask a Criminal Lawyer.
First you should contact the police and report it. Take immediate steps to live safely and try to alert your neighbors, friends and coworkers of the issue. Finally, you should obtain a camera and a audio recorder to document any future threatening behavior to show the authorities.
There are civil remedies available as well that depend on the nature of the threats and the context. Could you provide more information?
Once I have a few more details I'll be happy to supplement this answer with more information.
Very well. You should definitely report this to the police and like I said above... live safely for a while. Don't go out alone in the evenings, keep your doors and windows locked, and above all do not confront him if he actually shows up at your home or at work. Lock the door and call 911.
You can also petition the courts for a restraining order (this can normally be done pro se... without a lawyer). If you choose to do this without a lawyer then you can go to the clerk of your local courts and ask for an example or form petition. Normally they are willing to give you a blank form or at least an example of one that had recently been filed.
You should play these recordings for the police... it may be decided that they constitute a crime under one of Massachusetts harassment laws. He could actually be guilty of a crime already.
Please reply if I can assist further.
I would like to further point out that these people are usually all talk. I'm not saying that you shouldn't take it seriously, but don't get too worked up. People going through divorces and breakups are emotionally unbalanced and will say a lot of things that they don't mean. Obviously I don't know this guy... but know that the passage of time almost always calms the situation and ends the tension.
Still.... take precautions until things calm down.