No one knows for sure who killed JFK — here are the top theories

Just under 54 years ago, two years into his presidency, President John F. Kennedy was assassinated on a visit to Dallas, Texas.

An investigation by the Warren Commission determined a former US Marine named Lee Harvey Oswald shot Kennedy from a nearby book depository, but the murky facts of the case have led to a number of alternate theories.

They include a CIA conspiracy, a mafia hit job, a covert operation by Lyndon B. Johnson, and more.

In anticipation of the National Archives releasing 3,100 documents related to the assassination on October 26, here are the top theories that have swirled ever since.

See Also:

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SEE ALSO: Trump says he'll allow the release of more than 3,000 classified JFK files — here's what you need to know