The first time a nerve gas was used by a terrorist group was in

Iraq's use of mustard gas against Iranian troops and Kurds (Iran-Iraq war of 1981–1988) has been the only large-scale use of any chemical weapons. On the scale of the single Kurdish village of Halabja within its own territory, Iraqi forces did expose the populace to some kind of chemical weapons, possibly mustard gas and most likely nerve agents.

In the Gulf War, no nerve agents (nor other chemical weapons) were used, but a number of U.S. and UK personnel were exposed to them when the Khamisiyah chemical depot was destroyed. This and the widespread use of anticholinergic drugs as a protective treatment against any possible nerve gas attack, have been proposed as a possible cause of Gulf War syndrome.

One of the most widely publicised uses of nerve agents was the 1995 terrorist attack in which operatives of the Aum Shinrikyo religious group released sarin into the Tokyo subway system.