The Syrian military has loaded sarin nerve gas into aerial bombs that, if given the order by President Bashar al-Assad, could be dropped on civilians, NBC News reports.
Secretary of State Hillary Rodham Clinton said on Wednesday that if al-Assad found himself in a "desperate" situation, he might use the country's chemical-weapon stockpile, Reuters reports.
Clinton repeated what the Obama administration has said for the last several days: If Assad uses chemical weapons, the U.S. response would be swift.
Also on Wednesday, former Defense Secretary Robert Gates said President Obama is likely to enforce the threat. "I think it would be a mistake, particularly on Bashar Assad's part, to underestimate him," he said on CBS.