What to Know About Your Mailbox If You Live in An Apartment Building

It's a disturbing trend: with the turn of a single key, thieves can access the mailboxes of every resident in an apartment building and help themselves to valuable mail and packages. Incidents have been captured on camera in Los Angeles, Chicago and Canada. Somehow, all of these alleged thieves appear to have been able to obtain the master key to open the entire front panel. Master keys are supposed to only be available to postal employees, so how did these people get their hands on them?