The discovery of thousands of historic negatives belonging to war photography legend Robert Capa could end controversy over whether one of his most famous shots was faked.

The discovery of thousands of historic negatives belonging to war photography legend Robert Capa could end controversy over whether one of his most famous shots was faked.

The negative is thought to be contained in three cases of Capa photos which have turned up in Mexico, documenting the Spanish Civil War before Capa fled Europe for America in 1939.

Known as ?The Falling Soldier?, the 1936 picture ?shows a Spanish Republican militiaman reeling backward at what appears to be the instant a bullet strikes his chest or head’, reports the New York Times.

The image helped crystalise support for the Republican cause but sparked doubts over whether it was faked, adds the newspaper.

The negative has never been found ? subsequent images being reproduced from a ?vintage print?.

Housed in three ?flimsy cardboard? suitcases the archive represents the contents of Capa?s Paris darkroom.

The treasures had previously been considered lost forever.

Even Capa, who died in 1954 while on assignment in Vietnam, believed his work had been lost during the Nazi invasion.

The photographs will be stored at the International Centre of Photography in Manhattan, reports the New York Times.