By Ian Sparks  and Tim Finan PUBLISHED: 08:08 EST, 30 January 2013 | UPDATED: 14:28 EST, 30 January 2013 Germany has re-opened an investigation into the massacre of 642 French villagers by Nazi soldiers in one of the darkest chapters of World war Two. Almost the entire population of Oradour-sur-Glane, including 400 women and children, was gunned down or burned alive in a single day by SS troops on June 10, 1944. More than 68 years later, a German prosecutor and senior police officers have visited the abandoned village in central France, which Hitlers troops burned to the ground before they fled.
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452 women and children killed in Oradour-sur-Glane massacre
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Hitler's SS Panzer Division committed the atrocity on June 10, 1944
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It was to avenge death of German officer at hands of French Resistance
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Nazi commander told his 200 troops: ‘Today the blood must flow’
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Village left untouched since fateful day to serve as reminder of Nazi evil
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German authorities believe six Nazis in their late 80s are still at large
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Only one man, Heinz Barth, has ever been prosecuted for the attack
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He called for the shooting of 20 male villagers and received a life sentence
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Case was re-opened after discovery of documents implicating six suspects
out in revenge for the capture of a @placeholder officer by French resistance