At the time of Gaddafi, Libya was producing mustard gas in a clandestine manner in the Rabta chemical plant, 80 kilometers south of Tripoli. Experts estimate that Libya had also built a number of chemical weapons depots located throughout the country.
In 2004, as part of a rapprochement with the West, Libya has ratified the Convention on the Prohibition of Chemical Weapons, agreeing to destroy all its stocks.
According to estimates by the Organization for the Prohibition of Chemical Weapons (OPCW), Libya has succeeded in destroying 55% of its reserves of mustard gas before the start of the international operation against the Gaddafi regime on March 19.
According to data from the old Libyan government in March 2011, the country still had 25 tonnes of mustard gas and 1,400 tonnes of material that can be used to manufacture chemical weapons.