Islamic State making use of chemical weapons in Iraq, Syria: US official

The US has identified four occasions where they believe mustard agents were used on both sides of the Iraq-Syria border, adding that the chemical is being used in powder form.

A US official, on the condition of anonymity and a BBC team on the Turkey-Syria border claims to have seen evidence supporting these claims.

"They're using mustard," the individual said of Islamic State (IS), adding that "We know they are. "We've seen them use it on at least four separate occasions on both sides of the border - both Iraq and Syria."

Speculating the use of the mustard agents, the official said that the mustard agent was probably being used in powder form; packed into traditional explosives like mortar rounds. On explosion the mustard-laced weapons blister whoever is exposed to it.

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Although the intelligence community believes the most likely explanation is that the weapons are being manufactured, there are also theories that suggest that IS militants found caches of chemical weapons in Iraq and Syria.

"We assess that they have an active chemical weapons little research cell that they're working on to try and get better at it," the official said.

As the US government continues to investigate claims of chemical weapons, the BBC’s Ian Pannell, working from the Turkey-Syria border claims to have seen new evidence of chemical weapons being used in Syria.

However, a UN-backed deal ensured that the Syrian government handed over 1,180 tonnes of declared toxic agents and precursor chemicals to the Organisation for the Prohibition of Chemical Weapons (OPCW).

US Brig Gen Kevin Killea described sulphur mustard as a Class 1 chemical agent, which is seldom used outside of chemical warfare.

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An investigation into the use of chemical weapons in Syria was launched by the United Nations last month, which aims to find out which, governments, groups or individuals are involved in the use of the chemical weapons.

What is mustard agent?

Mustard gas is commonly used to describe an agent which is liquid at ambient temperature.

The agent, which can be clear to yellow or brown, can often be odourless or at times smell like garlic, onions or mustard.

Exposure to the gas, although not fatal, can cause blistering of the skin and mucous membranes on contact. People can be exposed through skin contact, eye contact or breathing if it is released into the air as a vapour, or by consuming it or getting it on their skin if it is in liquid or solid form.

Though exposure to sulphur mustard usually is not fatal, there is no treatment or antidote to mustard.

This article originally appeared on the BBC