War of the Monsters (1966) aka. Gamera vs. Barugon - movie trailer

Two Giant Beasts Clash in a battle for the world! Treasure hunters accidentally awaken the giant mythical beast Barugon, causing a rampage that decimates a modern city. Able to stop military weapons with his freezing death ray, the monster traces a path of destruction across the country. Prehistoric monster Gamera returns to Japan, igniting a devastating battle between the two fearsome creatures. Buildings burn and monuments topple as the war of the monsters rages and humanity is caught in the deadly crossfire. As earth's scientists fail to halt the onslaught, desperate citizens turn to the tribal folklore of Barugon's island in the hopes of saving civilization. War of the Monsters is the second installment in the Gamera series and the first to be filmed in color.