
Quoting
cdwjava
That's about all that comes to mind. Short of serving a subpoena on the carrier, Verizon (and that requires an active court case), there's not much you can do short of ignoring the calls.
- - - Updated - - -
It doesn't appear the OP has even checked with the police, yet. But, here's what the police will likely do: Take a report for PC 653m (annoying and harassing communications), give him a case number so Verizon might set up a phone trap if they can/will, MAYBE call the number and ask what's up and tell them to stop calling the OP, and then file the thing away. It's a low-level misdemeanor, and they are not going to serve search warrants on Verizon for this sort of thing where the OP thinks that it "appear(s)" they are planning an attack against him for some reason.