Rebel groups aligned with the Free Syrian Army  said they have created special units to monitor site where chemical weapons are stored, according to media reports on Monday.
The special units, "provide us with intelligence on any movement at those sites  and as soon as the regime falls, we have units tasked with securing the depots”, Rebel Brigadier General Salim Idris told Al Jazeera.
Recent weeks have seen increased fears over the potential use of any such weapons by Assad’s regime, with the US saying that if chemical weapons were used, it would constitute a “red line” and could force military intervention.
Israel's government, who have spoken out about fears that arms caches called fall in to the hands of Lebanon’s Assad-aligned Hezbollah, said in December that Syria’s chemical weapons stores remained secure .
Currently, there is no evidence to suggest that chemical weapons have been used  in the 21-month old conflict, which has claimed the lives of 60000, according the latest figures from the UN.