ye : ▁The ▁U nt old ▁Story ▁of ▁Jewish ▁Re ven ge ▁Again st ▁Germ ans ▁in ▁ 1 9 4 5 ▁is ▁a ▁ 1 9 9 3 ▁book ▁by ▁John ▁S ack , ▁in ▁which ▁S ack ▁states ▁that ▁some ▁Jews ▁in ▁Eastern ▁Europe ▁took ▁reven ge ▁on ▁their ▁former ▁capt ors ▁while ▁over see ing ▁over ▁ 1 , 0 0 0 ▁concentration ▁cam ps ▁in ▁Poland ▁for ▁German ▁civ ili ans . ▁S ack ▁provides ▁details ▁of ▁the ▁imprison ment ▁of ▁ 2 0 0 , 0 0 0 ▁Germ ans ▁" many ▁of ▁them ▁star ved , ▁be aten ▁and ▁tort ured " ▁and ▁estimates ▁that ▁" more ▁than ▁ 6 0 , 0 0 0 ▁died ▁at ▁the ▁hands ▁of ▁a ▁largely ▁Jewish - run ▁security ▁organisation ." ▁A ▁professor ▁of ▁Jewish ▁history ▁at ▁Bran de is ▁University , ▁Anton y ▁Pol ons ky , ▁said ▁that ▁his ▁" res earch ▁appears ▁to ▁be ▁sound ", ▁but ▁he ▁and ▁other ▁review ers ▁have ▁question ed ▁the ▁" ext ent ▁of ▁Jewish ▁per sec ution ▁of ▁Germ ans ", ▁in ▁S ack ' s ▁book . ▁ ▁Polish ▁histor ians ▁including ▁T ade usz ▁W ols za ▁from ▁the ▁Polish ▁Academy ▁of ▁Sciences ▁and ▁Kr z ysz to f ▁Sz w agr zyk ▁from ▁the ▁Institute ▁of ▁National ▁Rem emb rance ▁inform ▁that ▁in ▁ 1 9 4 5 – 1 9 5 0 ▁there ▁were ▁between ▁ 2 0 6 ▁and ▁ 5 0 0 ▁intern ment