The University of Iowa Veterans Association and Veterans for Peace organized the ceremony, on the campus of the University of Iowa in Iowa City on Friday, The Daily Iowan reported.
"[The purpose of the event] is first and foremost to honor those who died in the event and help out the survivors of the attack," the paper quoted Iowa Veterans for Peace coordinator Ed Flaherty as saying.
During the 1967 Six-Day War, Israeli forces launched an attack on Syria, Egypt, Jordan, and the Palestinian territories of the West Bank and the Gaza Strip and occupied vast swathes of Palestinian, Syrian, and Egyptian territories.
The United States dispatched the USS Liberty to spy on the communications of all parties engaged in the war.
The Israeli combined air and sea attack killed 34 crew members of the USS Liberty, wounded 170 others, and severely damaged the ship.
Israeli and U.S. government officials are still sticking to their position that the attack was due to a communications breakdown. However, former U.S. Rep. Paul Findley (R-Ill.) is convinced the attack was deliberate.
"The Israeli government almost succeeded in destroying an American Navy ship and blaming the attack on the Arab governments," he was quoted as saying in the same report.