The Late Show host was back behind his desk on Monday (22Aug11) following a two-week vacation, during which a man named Umar al-Basrawi urged fellow Muslims to ""cut the tongue of this lowly Jew and shut it forever"" after Letterman poked fun at accused terrorist leader Ilyas Kashmiri, who was killed during a U.S. airstrike in Pakistan in June (11).

The threat against the TV personality, who is not Jewish, was made on Shumukh-al-Islam - a popular Internet destination for radical Muslims.