Of the 2,331 confirmed incidents, 419 involved unauthorized possession and related criminal activities. Incidents included in this category involved illegal possession, movement or attempts to illegally trade in or use nuclear material or radioactive sources. Sixteen incidents in this category involved high enriched uranium (HEU) or plutonium. There were 615 incidents reported that involved the theft or loss of nuclear or other radioactive material and a total of 1,244 cases involving other unauthorized activities, including the unauthorized disposal of radioactive materials or discovery of uncontrolled sources. Of the total of 2,331 incidents reported, 91 involved natural uranium. This figure led the OECD’s Nuclear Energy Agency to conclude: “Even though the incidence of reports of this type of activity on an annual basis has been halved since the early 1990s, the continuation of reports shows that security and safeguards at uranium mines and mills can be improved even further.” (, p. 132).