I Have Read About This But Now I Have Proof

 During the 1863 New York City Draft Riots.  From Aug. 1, 1863 Harper's:

At Newspaper Row, across from City Hall, Henry Raymond, owner and editor of The New York Times, averted the rioters with Gatling guns, one of which he manned.  The mob, instead, attacked the headquarters of abolitionist Horace Greeley's New York Tribune until forced to flee by the Brooklyn Police.