US military spokesmen in Baghdad yesterday indicated a new trend in bombing attacks by Iraqi insurgents.

A pickup truck loaded with chlorine gas cylinders and explosives blew up in the southwest of the city, killing two Iraqis and wounding many more, according to the BBC.

Chlorine gas was a first-generation chemical weapon, used during World War I and in the Abyssinian colonial campaign of the 1930s, as well as on other occasions. It requires a relatively high concentration to be deadly so colossal quantities must be delivered to have useful combat effect. As a result, most national chemical-weapons programmes shifted emphasis to more efficient nerve agents in the post World War II era.

Industrial chlorine is widely used in Iraq for purifying water supplies, making it commonly available to insurgent forces.

The most significant physical effect of including chlorine gas cylinders with an explosive payload will typically be extra fragmentation damage, rather than associated poisonings.

Nonetheless, having achieved wider notice than deadlier conventional strikes, the tactic is clearly having a useful psychological effect. ®

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