A fire broke out inside a cooling tower near the National Museum of Natural History this morning, creating a large cloud of smoke over the National Mall which was visible for miles. The fire was reportedly located inside a structure which houses the museum’s cooling equipment. That building is is not attached to the main museum structure. WTOP’s Neal Augenstein reports that it was likely welding work which started the fire. The fire is now apparently under control, but traffic on Constitution Avenue NW between 9th and 12th Streets NW remains a mess due to a large number of fire trucks on the scene.