Left no msg. Called it back and said the number is unallocated.  Number is now blocked

There was a pause after I picked up.... then   a Woman  got on and said they were in the area installing solar panels and (This is where I hung up )

Caller ID said it was from the town of Worcester

       3-8-2016  Checked  the number and called it, ....it is as BDG  above stated   :      "UNALLOCATED"  Which indicates that they (Scammers)   will try and get personal information from you for their use on the first contact, or have you  send money by untraceable means to them.

The area code 878 is assigned to Penn.     Fake Phone ID used.......usually by domestic or foreign thieves

The" Call Type"  box menu should offer a scammer  choice in addition to Telemarketer