Berlin: Firefighters battled for hours to contain a blaze ?that engulfed the former Nazi guest house ?known as "The Eagle's Nest" in southern Germany, while police investigated the cause after detaining a man near the ?scene, authorities said on Saturday.Around 200 ?firefighters and emergency workers near Berchtesgaden in Bavaria were ?battling the flames after the building, known ?as the Kehlsteinhaus, caught fire on Friday, police ?said. Built in 1938 as a guest house for Nazi officials and their guests, the building sits in a spectacular Alpine ?setting above Berchtesgaden. Adolf Hitler used it occasionally, earning it ?the nickname "Hitler's Tea...