NYPD: Man wanted for robbing a mail carrier

The NYPD is searching for an individual who robbed a USPS letter carrier in Brooklyn.  
Police say that a 26-year-old female mail carrier was making deliveries around the 75th Precinct when an unknown male approached her, demanding the keys to the mailboxes.  
The man held the mail carrier at knifepoint when asking for the keys, according to law enforcement officials. The suspect in question is described as a male with dark complexion who is approximately 5 feet, 8 inches tall, and 40 to 50 years old. He was last seen wearing black pants.  
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477). 
The United States Postal Inspection Service provided the following statement:
“The Postal Inspection Service can confirm that a United States Postal Service Letter Carrier, assigned to Brooklyn, was the victim of the robbery. USPIS takes matters involving the safety and well-being of postal service employees as a top priority.  We are working diligently on this investigation. To protect the integrity of the investigation, we cannot provide further details at this time. If your readers have information, please contact us at 877-876-2455 (say “Law Enforcement”)  or via Twitter, @PostalInspector.”