Historians discover letters and numbers in Mona Lisa's eyes-monalisa101213file300_16gakb9-16gakbl-jpg

Tiny numbers and letters have been discovered painted into the eyes of the Mona Lisa prompting an investigation by art historians.

Members of Italy's National Committee for Cultural Heritage say the letters and numbers can be seen when magnifying high resolution images of the Mona Lisa'a eyes, the Daily Mail reports.

"To the naked eye the symbols are not visible but with a magnifying glass they can clearly be seen," Silvano Vinceti, president of the Committee, was quoted as saying.