Revealed: How Lee Harvey Oswald Planned Escape

Lee Harvey Oswald visited embassies in Mexico apparently planning his escape before he assassinated President John F Kennedy, according to newly declassified CIA documents.

Three days after the shooting in Dallas, Texas, on 22 November 1963, Lyndon B Johnson was informed that Oswald had visited the Cuban and former Soviet Union embassies in Mexico City on 28 September that year to arrange visas.

Oswald, a former US Marine who defected to the Soviet Union in 1959, used a sniper rifle to shoot President Kennedy in the head as he was driven through Dealey Plaza, Dallas, in an open motorcade.

He was arrested 45 minutes later on suspicion of shooting a police officer before being charged with killing Mr Kennedy. Oswald was shot dead by night club owner Jack Ruby two days later.

The report is among nearly 19,000 pages of newly declassified documents from the Cold War released by the CIA.

Many of the documents are stamped "For the President's Eyes Only" and were delivered to the White House.

Known as the President's Daily Brief, they are tightly guarded rundowns of CIA intelligence from around the globe.

Among the other documents was top-secret intelligence that a new warhead had been spotted in Cuba in 1962 as the US and Russia were on the brink of nuclear war.

But conspiracy theorists looking for CIA plots are likely to be disappointed as many of the intelligence briefs remain partially blacked out.

William Inboden, who worked under President George W Bush and leads the Clements Center for National Security at the University of Texas, said the memos reveal real-time intelligence which shaped decisions from the Bay of Pigs to Vietnam.

He said: "These are an incomparable window into how a president thinks.

"When we're reading these, it's a mirror image of what the president's concerns were."

The documents also reveal that the CIA published a second brief after Mr Kennedy's assassination.

It had no intelligence in it, only a poem the late president was fond of which read: "Bullfight critics ranked in rows/Crowd the enormous plaza full/But only one is there who knows/And he's the man who fights the bull."

They also contain intelligence briefings from Vietnam.

The release of the documents, posted on the CIA website, comes from a 2009 executive order by President Barack Obama that all classified material is automatically declassified and released after 25 years.