I’m a bit reluctant to contact the ‘authorities’. I mean, I did that once with the New South Wales Police Force (Australia) and Interpol and it was an unhappy experience. Once bitten, twice shy.
There are just so many ‘authorities’ out there. One such, is the Flipping Burgers Investigators. Just on their web site alone it’s hard to know if they want to be contacted, like ever. I mean, do they really want to be disturbed by seeing my Zodiac Cipher decryptions ? They’ve probably got better things to do anyway such as administrative paperwork or e-mailing each other.