A sterilization system for PET containers and bottles including at least one electron flow generator 1, a scan gun 2 and at least one target 4 preferably made of heavy metal, so that when a part of the electron radiation hits said target a reflected X ray radiation is generated, which contributes to the sterilization of the containers. A certain amount of liquid or gaseous oxygen which upon collision with the electron radiation is converted to ozone is also exposed to the radiation, thus further contributing to the sterilization.