Scam for money

I received a email from the Dept of Legal Affairs and Investigation.  It said I need to signed an agreement to settle a case under my ssn.  I have sent $900 dollars to Pay Pal on this account to the resolution.  Now I get a email stating I owe $780 to clear my ssn and if I don't pay this my ssn and house, car and bank account will be frozen.  It is coming from a Christopher Elk that suppose to work there.  I would like for someone to check on this.  I am not giving any more money.  I need to know is this a scam or not  and have I just lost my money.