A book that delves into the cover-up a film documenting the horrors suffered by victims of the atomic bomb attacks on Hiroshima and Nagasaki has been deemed too violent for Google's advertising program.

Greg Mitchell's new book, Atomic Cover-Up: Two U.S. Soldiers, Hiroshima & Nagasaki and The Greatest Movie Never Made, is the first to be devoted to the historic full-color footage that was covered up by the U.S. government for decades.

Google's "ad word team" notified Mitchell Monday that an online ad for the book's video trailer was being suspended because it "promotes violence."