There have also been a number of alleged UFO crashed retrievals, but most are not taken seriously. However, at the onset of the modern era in ufology there was a crash retrieval operation carried out near Roswell New Mexico USA which was initially reported by the USAF to have been of a crashed disk. The USAF later changed its story, maintaining that they had retrieved a weather balloon. In the decades following the Roswell incident, a number of ufologists gathered testimony from witnesses who maintain that the weather balloon story was a cover up for the real thing.