It was one of the most dramatic episodes of an American presidency -- the attempted assassination of President Ronald Reagan on March 30, 1981.
The recordings were requested by author Del Quentin Wilber for his book "Rawhide Down: The Near Assassination of Ronald Reagan." Rawhide was the code name for the President.
The assassination attempt happened at 2:27 p.m. as Reagan came out of the Washington Hilton Hotel.
Another Secret Service agent pushed Reagan into a limousine that fled the scene.
At first it seemed the president was okay and the limo took off for the White House.
But it was soon evident that Reagan had been hit, and the vehicle diverted to George Washington University Hospital.
The president would lose more than half of his blood, but he recovered and was able to return to the White House 12 days later.