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The campaign appears to have begun with a Weibo post by "Photographer" on Aug. 17 stating that "three hours by car from Xining [the capital of Qinghai Province] there are enormous crop circles!!" He goes on to explain the symmetrical nature of the pattern, the depth of the marks (3-5cm), and even names the driver (a "Master Zou") who said there were no marks there a week ago. Images are attached to his Weibo post, and so is a tantalizing portion of a video.
That snippet would also be used in the beginning of the official BMW advertisement released on Aug. 23 that revealed the deception. BMW explains its mischief alongside the video introducing the "1 Series" car. It says that the spirit of the vehicle--and its prospective drivers--is "UN1QUE," and that this fits in with the fake crop circle news because UFO stands for "UN1QUE For One."
Sina, a major news portal, revealed BMW's hidden hand behind the viral marketization of the commercial on Aug. 25. It was an unqualified success, having been mentioned on Sina Weibo over 300,000 times and gaining a huge share of BBS discussion and media coverage.
The deception had been carried out so well, apparently, that by Aug. 28 people were still wondering whether the "Qinghai Desert Circles" were actually an advertisement or not.
Some were furious with having been tricked. The comments section of the original posting on Weibo include statements like "Good people don't do this kind of thing," and "Shameless cheat!" It was unclear whether "Photographer" was a willing accomplice in BMW's plot, or how he had otherwise obtained the video snippet and the images. The apparently first-hand description originally given, and the liberal use of exclamation marks, seem to indicate the former.
The Chinese Communist Party's propaganda mouthpiece Xinhua was also taken in by the hoax. An article on Aug. 22 earnestly reproduces the pictures and, as though they had actually sent reporters to the scene, adds that "These circles... are much larger than 'crop circles', and much more magnificent to look at." Four days later, on Aug. 26 a Xinhua article explained to readers what the mysterious images are.