Warsaw gets poison gas conscious , by order of the government . Population plays at war . The authorities arranged an elaborate anti - poison gas drill in Warsaw , the Polish capital and the entire population had to co-operate . The citizens were asked to act just as they would if the attack were genuine and even the traffic policemen wore gas masks . The streets were deserted as the population took ' refuge ' and the first aid organisations demonstrated their efficiency . Photo shows , police wearing gas masks during the mock gas attack on Warsaw . 1 December 1933