BRITAIN'S Prince Harry will not be allowed to fight on the front line in Afghanistan, The Mail on Sunday newspaper says, citing senior sources in the prince's regiment. Harry, third in line to the throne, reportedly threatened to quit the British Army if he was blocked from active service due to safety fears and any such decision is likely to infuriate the 22-year-old. Although a formal decision has yet to be made, sources in the Household Cavalry told the weekly tabloid they thought it was too dangerous for him to deploy in Afghanistan. The southern Helmand province, where the bulk...