LOUISVILLE, Ky. (WHAS11) -- A federal investigation is underway after an attack on a mailman.

The Postal Service confirms one of its employees was involved in an assault incident in the 3400 block of Vermont, between 8 and 9 a.m. on Monday, Dec. 5.

The carrier was getting packages out of his vehicle when a male subject came up behind him, put something cold to his neck and said something to the carrier, USPS said. The carrier then turned around to face the subject but the subject ran, according to USPS. USPS says that is when he noticed he was bleeding from his neck.

The carrier returned to his Westport Road Post Office to report the incident.

Officials say the carrier was talking with postal investigators and was treated by EMS at the post office.

This appears to be a random attack, USPS said.

If the subject is found, the inspector said they will work with the prosecutor to press charges.

Anyone with information on this incident is asked to call 877-876-2455.