Authorities say a St. Paul man has pleaded guilty in connection with the gunpoint robbery of two letter carriers in the Twin Cities last month. Court documents say that Rubin David Adams, 26, pleaded guilty to two counts of armed robbery of a mail carrier. Court documents say that on Nov. 18, Adams helped another person who pointed a gun at a letter carrier in Edina and demanded a “mailbox key,” which the postal employee did not have. Instead, the employee handed over two sets of U.S. Postal Service vehicle keys. The next day, court documents alleged that Adams approached another letter carrier, this time in Brooklyn Center, and pointed a gun at the victim’s head demanding mailbox keys. Authorities say mailbox keys are valuable to criminals because they will use them to steal mail, cash, checks and other financial documents. It is a federal offense for an unauthorized person to possess one, according to the U.S. attorney’s office. Adams’ sentencing hearing will be scheduled at a later date. Related Articles Crime & Public Safety | Dead woman’s family files federal lawsuit against ex-trooper charged in Rochester collision Crime & Public Safety | Federal judge allows Derek Chauvin’s counsel to obtain George Floyd tissue, fluid samples Crime & Public Safety | Hastings man charged with multiple counts of child pornography Crime & Public Safety | Former St. Paul charter school substitute teacher charged with sexual misconduct with student Crime & Public Safety | Adam Fravel sentenced to life with no parole for killing Madeline Kingsbury