 The events in My Lai were initially covered up by the U.S. Army.In April 1969, nearly 13 months after the massacre, Ron Ridenhour, a GI who had been with the 11th Brigade, wrote letters to the President, Chairman of the Joint Chiefs of Staff, the Secretary of Defense and 30 members of Congress.In these letters Ridenhour described some of the atrocities by the soldiers at My Lai that he had been told about.