A veteran journalist is casting further doubt on Bill O’Reilly’s claim that he was an ear-witness to the 1977 suicide of George de Mohrenschildt, an associate of Lee Harvey Oswald’s who was investigated after the assassination of President John F. Kennedy.

Writing in Newsweek Monday, Edward Jay Epstein, an investigative journalist, said the Fox News personality could not have been near the death scene in Manalapan, Florida, as he claimed to be in his best-selling 2012 book “Killing Kennedy: The End of Camelot.” On the contrary, Epstein writes, “I was the actual -- and only -- reporter interviewing de Mohrenschildt on the last day of his life in 1977.”

Epstein, who published a biography of Oswald in 1978, claims he interviewed de Mohrenschildt at a hotel in nearby Palm Beach just hours before he was found dead of a self-inflicted gunshot wound. After the suicide, Epstein said he obtained the investigative file for the case from the state’s attorney. He also claims to have spoken with de Mohrenschildt’s family, including his daughter Alexandra. “From what I learned about the case, O’Reilly’s story does not fit the facts,” Epstein wrote.

In his book, O’Reilly tells an anecdote in which -- as a young television reporter -- he tracked de Mohrenschildt down and was outside the door of his daughter’s home when he “heard the shotgun blast that marked” the suicide. But according to the police report, Epstein wrote, no one inside or outside the house actually heard the gun go off. 

A spokesperson for Fox News referred us to O'Reilly's publisher, Henry Holt, an imprint of Macmillan. On Monday, the publisher posted a detailed statement from Bob Sirkin, a former reporter for WFAA-TV in Dallas who accompanied O'Reilly to Florida to cover the story. Sirkin asserts that he and O'Reilly were in Florida before, during and following de Mohrenschildt's death. 

Discrepancies in O’Reilly’s de Mohrenschildt anecdote were first brought to light on the website JFKFacts.com, where Jefferson Morley, the site’s editor, posted an audio conversation between O’Reilly and an investigator that was purportedly recorded on the day of George de Mohrenschildt’s death. In the recording, O’Reilly can be heard being told about the suicide and saying he plans to take a plane to Florida that night or the next day.

The JFKFacts report received little attention until last month, when the liberal watchdog Media Matters posted its own report on the same topic, citing JFKFacts along with former colleagues of O’Reilly’s. Later, CNN also aired the audio clip.

Newsweek is owned by IBT Media, parent company of International Business Times. Read the full Newsweek story here.

This story has been updated with input from Fox News and Henry Holt.