The uranium – believed to be of high quality – stems from a project to build a nuclear facility with the help of North Korea at Al-Kibar.
Intelligence agencies believed that the reactor was close to completion, but the site was destroyed by Israeli warplanes in September 2007:
"An IAEA inspection team visited the destroyed Al-Kibar site in May 2008 and only found traces of uranium. This merely added to the mystery of where the 50 tons of uranium, if it exists, might be. Such a stockpile would be enough, according to experts, to provide weapons grade fuel for five atomic devices.
"Some government officials have raised concerns that Iran, which is closely allied to the Syrian regime and urgently needs uranium for its nuclear programme, might be trying to seize such a stockpile.
"These officials’ fears have been triggered by signs of movement at what they allege is a secret uranium conversion facility that the Syrian regime built at the town of Marj al-Sultan near Damascus."