I SOVIETS CLAIM MANY AMERICANS, BRITQN5 KILLED BY GERMANSLondon, Dec, —The Moscow radio said today an extraordinary Soviet commission had established that nearly 700,000 persons, including an undetermined number; of Americans and British from Ger-! man prison camps, were torturedj and slain in the Nazi extermination camp at Lwow.The broadcast, recorded here by the soviet monitor, said an additional 200,000. persons were killed in another Nazi camp ai.Janow. And that children were slaughtered In target practice. 'The broadcast did not make dear whether the British and American* were prisoner* of wo r or civilians And did not state their number.