UN nuclear watchdog: 2.5 tons of uranium missing in Libya

DUBAI, United Arab Emirates -- Some 2.5 tons of natural uranium stored in a site in war-torn Libya have gone missing, the United Nations nuclear watchdog said Thursday, raising safety and proliferation concerns.

Natural uranium can't immediately be used for energy production or bomb fuel, as the enrichment process typically requires the metal to be converted into a gas, then later spun in centrifuges to reach the levels needed.

However, each ton of natural uranium — if obtained by a group with the technological means and resources — can be refined to 5.6 kilograms (12 pounds) of weapons-grade material over time, experts say. That makes finding the missing metal important for nonproliferation experts.

In a statement, the Vienna-based International Atomic Energy Agency said its director-general, Rafael Mariano Grossi, informed member states Wednesday about the missing uranium.

The IAEA statement remained tightlipped through much of the details.