(Newser) – Oops. CNN reports a federal air marshal left her gun in the bathroom during an April 6 Delta flight from England to New York. The gun was found by a passenger, who fortunately handed it over to the flight crew. The air marshal failed to report the incident to her superiors for a number of days and apparently wasn't punished when she did, according to the New York Times. Former and current air marshals says she should have been. "If someone with ill intent gets hold of that weapon ... they are now armed," one former air marshal says. The incident could be used as further fuel for critics of the air marshal program, which costs nearly $1 billion per year, covers less than 1% of domestic flights, and has apparently not prevented any acts of terrorism. (Read more Federal Air Marshal Service stories.)