The United States National Archive has released previously lost recordings made in the confusing and anxious hours immediately following the assassination of President John F Kennedy.
The BBC reports the tapes contain 42 minutes of audio material donated by a rare documents dealer who acquired them from an estate sale of a Kennedy aide.
They include dramatic conversations aboard Air Force One, during which the newly sworn-in president Lyndon Johnson is returning to Washington from Dallas with President Kennedy's body.
Mr Johnson can be heard consoling the dead president's mother, Rose Kennedy.
"I wish to God there was something I could do," he says. "And I wanted to tell you that we are grieving with you."
The tapes also include audio of attempts to contact Secretary of State Dean Rusk and other cabinet members in an aircraft over the Pacific en route to Asia to inform them of President Kennedy's death.
"This is the Situation Room," an official says, "....we have report quoting that the president is dead, that he died about 35 minutes ago."
