A two-alarm fire Sunday morning on the 11th floor of a building in the 12000 block of Sunset Hills Road has been contained, officials say. The fire started in a cubicle, Deputy Chief Dan Shaw said. “Upon arrival, [firefighters] found a working fire on the 11th floor,” he said. “The fire was being contained by a sprinkler system that had successfully activated.” Units from Fairfax County Fire and Rescue stations 4 and 36 responded. The second alarm was sounded for resources, Shaw said. The cause of the fire remains under investigation. We will provide more information when it becomes available.