The body of US president John F Kennedy should be exhumed for analysis by forensic experts to see if he was the victim of a military-style ambush by several assassins, a British author said last night.Matthew Smith's call is backed by Cyril Wecht, America's former top pathologist who once led the country's academy of forensic sciences.Mr Wecht sensationally discovered the president's brain was missing when he conducted an examination of highly sensitive autopsy evidence, but says his skull and remains should still be available for analysis.As the world remembers the 50th anniversary of the assassination this Friday, Mr Taylor says the macabre demand could finally resolve the greatest mystery of the past century.Highly respected Mr Wecht has written a foreword for Mr Taylor's fifth book on the tragedy, called simply Who Killed Kennedy?Retired college lecturer Mr Smith has spent decades analysing all known information and is convinced Lee Harvey Oswald, 24, was not the real killer.Mr Smith writes: "First, the members of the Kennedy family who have records placed in their protection must reveal those for public scrutiny."Second, as painful as it may be, President Kennedy's remains must be exhumed and re-examined, this time by the top pathologist in the nation. We will then learn about the direction of the gunfire, which will result in a decision on whether a new, thorough investigation is warranted."These would appear to be the essential steps towards this country coming to terms with the nagging questions which have plagued it since Friday, November 22, 1963."Until then, there can be no expectation of truth for the living, nor justice for the dead."The Warren Commission's official version of what happened is that former marine Oswald took his 6.5mm Italian rifle to the sixth floor of the Texas School Book Depository, where he worked.As the open-top presidential Lincoln car containing Kennedy and his wife Jackie drove down Elm Street, he fired several shots. One hit the president in the upper back and exited through his throat and the other hit his head, taking half his brain away.Troubled Oswald once lived in Russia and had a Russian wife, Marina, and was a critic of Kennedy's policies towards communist Cuba.Mr Smith believes Oswald was a CIA spy, who was also doing shady work for the FBI.He believes the shot to his back did come from the sixth floor of the depository or another nearby building, but Oswald was not the shooter.He also claims two other rifle shots came from two different positions on the grassy knoll to the front and right of the presidential Lincoln, the first bullet hit him in the throat.The fatal shot, he says, came from another assassin on the knoll and entered his right temple before exploding out of the rear of his head.By law the post-mortem examination on the president's body should have been carried out in Dallas, where he was killed, but the body was flown to Washington and the autopsy carried out at Bethesda Naval Hospital.One witness at the scene reported that the president had been shot in the temple. One of the surgical team trying to save his life at Parkland Hospital in Dallas said he saw a round hole entry point by his temple but that was never properly recorded.If he was shot in the right temple, the assassin must have been ahead of the presidential car in the knoll area.Mr Smith said: "An examination of the skull would establish whether a bullet did enter his head at the temple, which would disprove the theory that the fatal injury came from behind."My belief is that several people were involved in a well coordinated ambush which had elements of military planning."More than 10 witnesses reported hearing shots coming from the knoll.Another key fact which has never been satisfactorily explained is that a deputy sheriff swore that the rifle found in the depository was a German Mauser and not Oswald's Carcano rifle.Moments after the sound of shots were heard a police officer ran into the depository and saw Oswald, who was on the second floor. Saying he would not now get any work done, Oswald left the building soon after.Incredibly, the police issued an all points bulletin on him within 15 minutes of him leaving the building.An officer who saw him 40 minutes later was shot dead by Oswald, who was arrested for that crime only.He was later charged with killing the president but denied both charges and, as the world knows, never gave his account in court. He was gunned down by nightclub owner Jack Ruby two days later.Who Killed Kennedy?, by Matthew Smith, is published by Mainstream and costs £20.