The United Nations' nuclear watchdog agency says tons of highly radioactive nuclear waste from a defunct Serbian facility have been successfully shipped back to Russia in a secret, high-security operation.
The UN International Atomic Energy Agency (IAEA) said 2.5 metric tons of the spent fuel arrived December 22 at a secure Russian facility from Serbia's Vinca reactor near Belgrade.
The waste material is reported to include 13 kilograms of uranium enriched at a level close to that used to make nuclear warheads.
Reports said the material represented a high safety risk.
An IAEA statement said it took more than a month for the material to arrive at the Russian reprocessing facility in the largest single shipment of its kind.
The operation is reported to have been carried out by Serbia and coordinated by the UN nuclear agency with assistance from Russian, U.S. and European Union funding.
compiled from agency reports