The mystery is based on a series of strange events that take place on Vice Beach in GTA Vice City Stories. As evident from multiple pieces of video evidence, upon causing chaos in the beach, running pedestrians get trapped under the sand. This event may be explained with the help of glitches or faults in the level geography.
One of the other events is that if the player shoots one of the pedestrians on the beach, other pedestrians get shot automatically. Another incident includes when numerous deaths occur randomly on the same place without any possible explanation. This is yet to be explained by technical experts.