In the afternoon of the third day of the war, the American SIGINT spy ship "USS Liberty", outfitted by the NSA, was attacked by Israeli warplanes and torpedo boats in international waters north of Sinai. This U.S. Navy ship was severely damaged with loss of life. The Israelis quickly notified the Americans and later explained that they "had mistaken the "Liberty" (455 feet long) for the Egyptian coastal steamer "El Quseir" (275 feet long). The US government formally accepted the apology and the explanation." Some continue to accept this position. Yet "scholars and military experts," according to author Thomas Powers, state that "the hard question is not whether the attack was deliberate but why the Israelis thought it necessary." About the "Liberty" Helms in his memoirs quotes the opinion of his deputy, DDCI Rufus Taylor, and mentions the conclusion of a board of inquiry. Then Helms adds, "I have yet to understand why it was felt necessary to attack this ship or who ordered the attack".