By Steven Jiang, Mike Valerio, CNN A small aircraft appeared to have struck the tallest building in China's capital on Friday afternoon (local time), in a shocking incident in one of the world's most fortified cities. Dramatic footage from Beijing posted on social media showed debris falling from the 109-story CITIC Tower, also known as China Zun, as well as a tail section of the plane and a broken window of a taxicab on the ground.