The Kennedys ride a limousine through Dallas on Nov. 22, 1963. Secret Service Agent Clint Hill walks beside the vehicle behind them, in a black suit and sunglasses.Photo: Bettmann Archive

Sixty years after the assassination of PresidentJohn F. Kennedy, former Secret Service AgentClint Hillremains steadfast in his belief of what happened that day: “One man, one gun, three shots.”
To mark the milestone anniversary of Kennedy’s death, Hill is releasing a new commemorative edition of his best selling bookFive Days in November— co-written with his wife, Lisa McCubbin Hill — including a very personal afterword addressing the ongoing conspiracy theories and misinformation surrounding what happened in Dallas six decades ago.
“Right now, there are very few people left who were present that day and we’ll all be gone soon and there will be no one left to tell the facts,” Hill, 91, tells PEOPLE. “I thought it was important to get this out there — the factual documentation of what happened on Nov. 22, 1963.”
Jackie and Jack Kennedy descend the steps of Air Force One after arriving in Dallas on Nov. 22, 1963.White House Photographs/John F. Kennedy Presidential Library and Museum, Boston

White House Photographs/John F. Kennedy Presidential Library and Museum, Boston
Few had a closer look at the tragic events than Hill, who was assigned to first ladyJackie Kennedy’s detail in 1960. Accompanying the Kennedys to Dallas, he was in the motorcade — in the car behind the president’s — as they made their way to the trade mart where the president was scheduled to give a speech.
“All of a sudden, I heard an explosive noise from over my right shoulder,” he recalls. “I began to turn but my eyes remained fixed on the president. He grabbed his throat and fell to his left. I jumped off and ran to try and get to him, to Mrs. Kennedy, to form a barrier to protect them.”
By the time he did, the third shot had hit the president’s head.
“I started to get on the back of the car about the same time that the car accelerated, I got one foot up and then I slipped off and had to take three more steps to get to a position where I could get up again, and I did,” recalls Hill. “I pulled myself forward and threw myself on to the vehicle, just as Mrs. Kennedy is coming up on the trunk. Luckily I made it.”
Clint Hill climbs onto the presidential motorcade as gunfire rings out. Jackie Kennedy crawls toward him, her husband slumped over in the limousine.ZAPRUDER FILM 1967 (Renewed 1995) The Sixth Floor Museum at Dealey Plaza

Hill agrees with the Warren Commission’s conclusion thatLee Harvey Oswaldwas the lone shooter.
As for the manyconspiracy theoriesthat continue today — that there was more than one shooter, that the CIA may have been involved, that abullet found on a hospital gurneyhas hidden significance, to name a few — he calls them just that: “Theories, not facts.”
As he writes, “Everyone had his or her own opinion, which was often based on political leanings or hearsay.”
Adds McCubbin-Hill, “The many conspiracy theories grasp at different pieces of evidence, often leaving out relevant information and first hand accounts of Clint and others who were there.”
Jackie and John Kennedy in Dallas on Nov. 22, 1963. Secret Service Agent Clint Hill stands centered in the background.Fort Worth Star-Telegram Collect

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All these years later, he admits, “There’s never been any closure. I’m reminded of it every day, whether it’s a photograph or a magazine or newspaper.”
“I should have done more," he adds. “I should have gotten there quickly, but I know I’m not faster than a speeding bullet. But that causes me guilt that is difficult to live with.”
source: people.com