Britain tried to kill Adolf Hitler using a secret army of 4,000 children. An army of "ruthless" youths aged between 12 and 15 were turned into baby-faced assassins by MI6 agents as part of a network of saboteurs and spies recruited as Britain prepared for Operation Sealion - Hitler's 1940 plan to invade the UK - by trying to murder the Nazi dictator. Historian Andrew Chatterton said: "They were equipped with rifles and girls were shown how to use garrottes. "This isn't 'Dad's Army'. This is a highly prepared and utterly ruthless post-invasion team. "MI6 secretly set up these groups...