In 1967, Israel attacked a US spy ship, killing 34 men and injuring many more. The Israelis claimed it was an accident, the Americans backed them up. Both governments concealed the horrific truth. As the [USS] Liberty sat within eyeshot of El Arish, eavesdropping on surrounding communications, Israeli soldiers turned the town into a slaughterhouse, systematically butchering their prisoners. In the shadow of the El Arish mosque, they lined up about 60 unarmed Egyptian prisoners, hands tied behind their backs, and then opened fire with machine guns until the pale desert sand turned red. This and other war crimes were just some of the secrets Israel had sought to conceal since the start of the conflict. An essential element in the Israeli battle plan seemed to have been to hide much of the war behind a carefully constructed curtain of lies: lies about the Egyptian threat, lies about who started the war, lies to the US. Into this sea of deception and slaughter sailed the USS Liberty, an enormous spy factory loaded with the latest eavesdropping gear. The order was given to kill her and at 12.05pm, three motor torpedo boats from the port of Ashdod, about 50 miles away, departed. Israeli air force fighters, loaded with 50mm cannon ammunition, rockets and napalm, followed. According to information, interviews and documents obtained, for nearly 35 years the NSA has hidden the fact that one of its planes - a Navy EC-121 ferret - was overhead at the time of the incident, eavesdropping on what was going on below.