Surveillance camera caught a tenant stealing package from another tenant.

I installed a surveillance system in my six unit apartment building a couple of months back and recently received a request from a tenant to investigate a missing usps package.   What I found was a boyfriend of another tenant took the package.    

Now I do not know how to handle the situation.   Do I give the tenant who's boyfriend stole the package a heads up or do I give the information to the tenant with the missing package the tape, or do I contact the police directly. 

Any help with this is appreciated.