Italian scientists have found a matching image of a man's face and possibly his hands on the back of the Turin shroud, believed by many to be the burial cloth of Jesus Christ, one of the researchers said on Thursday.

The discovery that the ghostly image on the back of the linen cloth matches the face that adorns the front is likely to reignite debate over whether the shroud is genuine or a skilful medieval fraud.

"The fact that the image is two-sided makes any forgery difficult," Professor Giulio Fanti of the University of Padua told Reuters.