The U.S. National Archives on Thursday released thousands of documents related to the 1963 assassination of then-President John F. Kennedy shortly after President Joe Biden issued an executive order authorizing the release that also kept hundreds of other sensitive records secret.

Kennedy was shot and killed while riding in his motorcade through Dallas on Nov. 22, 1963, at the age of 46.

An investigation led by Chief Justice Earl Warren concluded that Lee Harvey Oswald, a former Marine and communist activist who had lived in the Soviet Union, acted alone. However, the probe has been widely criticized by academics and historians in the nearly 60 years since the assassination.

Thousands of books, articles, TV shows and films have explored the idea that Kennedy’s assassination was the result of an elaborate conspiracy. None have produced conclusive proof that Oswald – who was fatally shot by nightclub owner Jack Ruby two days after killing Kennedy – worked with anyone else, although they retain a powerful cultural currency.

Congress in 1992 had ordered that all remaining sealed files pertaining to the investigation into Kennedy’s death should be fully opened to the public through the National Archives in 25 years, by Oct. 26, 2017, except for those the president authorized for further withholding.

In 2017, then-President Donald Trump released a cache of records, but decided to release the remaining documents on a rolling basis.