The International Atomic Energy Agency (IAEA) has detected particles of highly enriched uranium at a nuclear research site in Egypt, according to a report on Wednesday.
The traces were found in 2007 and 2008 in samples taken at the Inshas research reactor, said the agency in its annual report on its nuclear inspection activities.
Egypt has told the IAEA that it believed the particles came to the country as contamination on containers of radioisotopes, a claim that is being investigated by the Vienna-based organization.
The report did not state whether the uranium was enriched to such a high degree that it could be used for nuclear weapons.
Radioisotopes are used in medicine and industry, and can be produced in reactors powered by highly enriched uranium.
In a separate investigation started in 2004, it was revealed that Egypt had failed to report various nuclear experiments to the IAEA.