The AGTR-5 USS Liberty was a Belmont-class technical research ship, belonging to the United States Navy. The most notable event concerning her was the "Liberty Incident." This was a series of attacks on her in international waters near the Egyptian town of El Arish on June 8, 1967, during the Six Day War, by Israeli fighter planes and torpedo boats. The attacks killed 34 US servicemen and wounded 173, making it the second deadliest attack against a US warship since the end of World War II. The captain of the ship, Commander William McGonagle, was awarded the Medal of Honor for his actions during and after the attack after the State Department had confirmed with the Israeli Embassy that Israel had no objections to the award. The government of Israel eventually paid almost $13 million in compensation, against total US claims of around $40 million, to the U.S. government and the families of the victims. Congress increased Israel's annual aid to cover these payments.
The attack is still a subject of controversy. Many people, including the surviving crewmen "to a man," believe that the Liberty was targeted deliberately, and that her attackers knew she was an American ship. It has also been claimed by the survivors of the attack that after launching five torpedoes at the ship the Israeli torpedo boats closed in and machine-gunned liferafts which had been launched by Liberty's crew, and that the aircraft which attacked the ship with rockets, napalm and gunfire used jamming in an attempt to prevent her sending a distress message. Dean Rusk, U.S. Secretary of State at the time of the incident, wrote: "I was never satisfied with the Israeli explanation... Through diplomatic channels we refused to accept their explanations." 
Israel maintains that the attack was accidental, and that the Liberty was mistaken for an enemy vessel (either a Soviet-built destroyer, an Egyptian horse transporter half the size of the Liberty or an even smaller British-built Hunt-Class destroyer, according to various IDF sources.) Prior to the first attack the Liberty was overflown eight times by Israeli reconnaissance aircraft. In the IDF official report into the incident it was acknowledged that the IDF had identified the Liberty as a US monitoring ship at least three hours before the attack, but that this information had "gotten lost." Despite this admission, an Israeli court ruled that no member of the IDF had been negligent.
- The USS Liberty: America's Most Shameful Secret.
- Liberty Memorial.
- Obama Threatened to Shoot Down Israeli Jets Attacking Iran. A Liberty in reverse.
- The vessel's specification
- Raid on the Sun, by Rodger W. Claire, Random House, 2004
- Dean Rusk. As I Saw It. New York: W.W. Norton, 1990. ISBN 0-14-015391-8 page 388.