Disturbing scene in Maryland over the weekend ... some scumbags vandalized a high school football field with racist language -- and now, cops say they're on the hunt for the culprits.

The graffiti was sprayed near the 50-yard line at Calvert High School's football stadium in Prince Frederick, MD. ... with the several racist messages including, "F**k n*****s."

Community leaders said in a Facebook post a 15-year-old Black student discovered the vandalism early Sunday morning ... and believe it "may possibly be a response to a picture" of the school's football coach supporting the H.S.'s new Black principal.