I was just informed by a friend that my gas cap was left off my airplane. I said I must have left if off after I filled it. He then said the tanks are empty and he called the police. I let a few other buddies who park at the airport know and one of them was hit as well and his cap left off. His tanks filled with snow and ice requiring a thaw job and he also filed a police report. I called the Public Works Department as well who said another person was hit this past weekend.