(NewsNation) — A new first-hand account of President John F. Kennedy’s assassination in 1963 brings into question the “magic bullet” theory, re-writing one of the most important days in modern American history.

Paul Landis was one of the Secret Service agents on the scene, positioned just feet away from the 35th president at Dealy Plaza on November 22, 1963.

In a new interview, Landis tells a version of the story that goes against the official account, and even his own previous statements.

Landis told the New York Times although he always believed Lee Harvey Oswald acted alone, “I’m beginning to doubt myself now, I begin to wonder.”

The Warren Commission, an 889-page final report on JFK’s assassination, determined that a single bullet struck the president from behind, exited through his throat and continued on to hit Texas Gov. John Connally.

However, Landis says he found a bullet stuck in the limousine seat behind where Kennedy was sitting, which he then put on his stretcher.

Landis says he believes the bullet didn’t penetrate Kennedey’s back deeply, and fell out before he left the vehicle.

His account of the event, included in his upcoming memoir, raises questions of its own, including why he waited 60 years to tell his story and how reliable his memory is after all these years.

Despite this, Landis was a first-hand witness, and “his mind is clear and his recollections steady,” according to his interviewer.

“There’s no goal at this point,” he said in an interview last month in Cleveland. “I just think it had been long enough that I needed to tell my story.”

This comes as the Biden administration released more than 16,000 documents related to JFK’s assassination.