Someone in china and/or russia is using my full name, my mailing address and my old but invalid phone number as contact info on their multiple domains registrations on Whois.

Email address that is posted on Whois is someone elses, not mine. IP is in russia, registrar is BIZCN(dotcom), Inc. which is in china.

Some of those hosting servers are some kind of public servers.
Host for that domain is FREEDNS.WS registered at whois.publicdomainregistry.com

To make matters annoying as the least I just received a letter from a U.S. attorney asking me to stop using domain of their client, which is very similar to a known company name.

Since this is a first time I discovered that someone (under russian, European and other worlwide IP servers!) has registered a big number of domains and are all listing them under my name, but since I never registered those domains nor paid for them nor I have access to their management I feel helpless to help this UNPROFESSIONAL lawyer in Manhattan, who did not make any research who the real owner is or could be and already threatens me with huge fines and only gave me 7 days to respond, that is including arrival time of his letter and for my letter to reach him! The attorney mails his letter to me on Oct. 10 which goes to another distant state in the deep countryside and expects to receive a reply by Oct. 17 !? It sounds like a frivolous and or propped up accusations, non-meritorious claim or some kind of a new scam.

First of all what is to be gained by using someone else's name on their domain registrations?

Second what do you think of all this?

I'm not asking for legal advice, but since my income is very small (wrong guy to cash out with) I will appreciate any legal advice as well if any lawyers here.

Thank you in advance for your opinion, advise and help.