The Organisation for the Prohibition of Chemical Weapons (OPCW) supervised the destruction of Libya's chemical weapons caches through February 2011, when it was forced to suspend its operations due to the uprising against Gaddafi and the resulting deterioration of the country's stability. By then, Libya had destroyed 40% of its precursor materials and 55% of its mustard gas, as well as 3,500 chemical weapon munitions. In early September 2011, OPCW Director-General Ahmet Üzümcü said reports he had received indicated that the remaining weapons were secure and had not fallen into the hands of militant groups. A stockpile of mustard gas, which the OPCW reported the regime may have attempted to hide from inspectors overseeing the chemical weapons program's dismantlement, was reportedly found in the Jufra District by anti-Gaddafi fighters less than two weeks later. In late September it was reported by the "Wall Street Journal" that a major ammunition complex, including chemical-weapons-capable artillery shells, was unguarded and open to looting. In December 2012 a senior Spanish intelligence official said that Al Qaeda in the Islamic Maghreb "probably also has non-conventional arms, basically chemical, as a result of the loss of control of arsenals", with Libya the most likely source.