The newly released U.S. government files on the JFK assassination include some fascinating information. Here are three of the released documents that shed some light -- and raise more questions -- about what happened before and after President Kennedy was killed.

The Soviets called Lee Harvey Oswald a "maniac"

An FBI document from 1966 sheds some light on how American intelligence perceived the Soviet reaction to Kennedy's assassination. Citing several sources, the document lays out the "great shock" of the Soviet people and leadership, and their fears that JFK's death could lead to war with the U.S.

The Soviets seem to have been convinced that Oswald was no lone gunman, and was likely part of a "coup" launched by the American "ultraright." They also professed to have a low opinion of Oswald, who defected to the Soviet Union in 1959. Oswald, a former Marine who had worked at sensitive U.S. military installations in Japan, was apparently seen by the Soviets as a "neurotic maniac who was disloyal to his country and everything else."

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Despite Cold War tensions, the Soviet leadership and intelligence apparatus also appeared to have a high opinion of Kennedy and knew little about his successor, President Lyndon Johnson. Figuring out "what kind of man" Johnson "would be" as president was, according to a source, a top priority for the KGB.

The Soviets were also anxious to not be blamed for the assassination, which came at a fraught moment for U.S.-Soviet relations. KGB guards were placed outside the U.S. embassy in Moscow to prevent any "disrespect" from being shown to the U.S. in the days following the assassination.

An odd call in Cambridge

A memo from James Jesus Angleton, the legendary head of the CIA's counterintelligence division, tells the story of a disturbing phone call placed to a newspaper in Cambridge, England just minutes before the assassination.

According to Angleton's memo, which was sent to FBI director J. Edgar Hoover, a man called a reporter at the Cambridge News to tell him that he should check with "the American Embassy in London for some big news and then hung up." Roughly 25 minutes later, President Kennedy was shot and killed in Dallas.

Angleton's memo goes on to say that the reporter immediately informed MI-5, the British domestic security service, about the call after news broke that Kennedy had been shot. "The Cambridge reporter had never received a call of this kind before and MI-5 state that he is known to them as a sound and loyal person with no security record," the memo continues.

The memo adds that MI-5 was familiar with "similar anonymous phone calls of a strangely coincidental nature" that had been reported by other British citizens over the previous year.

The FBI was trying to track Oswald before the assassination

A mysterious document from the FBI's New Orleans office express interest in tracking down Lee Harvey Oswald in the weeks before the assassination. The interest in Oswald appears to stem from his involvement in the New Orleans chapter of the Fair Play for Cuba Committee, a pro-Castro group.

The document, dated October 25th, 1963, discusses "contact" with "Cuban sources" about Oswald and what he was up to, as the Fair Play for Cuba Committee "appears to have become inactive" since he left New Orleans. An addendum notes that the report was sent to Dallas, where the FBI suspected he might relocate there to start another chapter of the pro-Castro group. Oswald would assassinate Kennedy in Dallas on Nov. 22.

Interestingly, Jack Ruby was also under some kind of FBI surveillance in 1962. Oswald was shot and killed by Ruby on Nov. 24, 1963.