Varan the Unbelievable (1962) avi

Commander Jim Bradley of the United States Navy is sent to Japan to test a chemical, which if successful, will be used to desalinate water. Unfortunately, the indigenous population are against the experiments in their lake, which happens to have the right amount of salt content, because it is feared that the chemicals will re-awaken their god, Obake. After Bradley's wife Anna intervenes, the populace is evacuated and the experiment goes on as scheduled. Unfortunately, as predicted, the chemicals reawaken their god, which happens to be a giant prehistoric beast. After destroying the local village, the creature then sets his sites on the city of Oneida.