IS suspected of chemical attack on US troops in Iraq

ISLAMIC State militants are suspected of firing a shell loaded with a chemical agent during an attack on US and Iraqi troops in northern Iraq on Tuesday, a Pentagon spokesman said.

If confirmed, it would be the first recorded chemical attack on US troops since the Islamic State overran parts of northern and western Iraq in 2014.

According to Navy Captain Jeff Davis, only one of the shells lobbed at Qayyarah Airfield West, where US troops are based, tested positive for a mustard agent. There were no US casualties, Davis said, and the shell, “likely a rocket or mortar, was imprecise and crude”.

No service members showed any signs of mustard agent exposure, Davis added. Concentrations of mustard gas can cause agonising burns and blisters, blindness and permanent disfigurement. US troops often deploy with protection against chemical weapons, including gas masks.

In the past, when investigating chemical weapon attacks, US forces have conducted a preliminary investigation of the weapon in the field before sending it for extensive lab testing and analysis.

Qayyarah AirfieldWest, also known as Key West, was retaken by Iraqi security forces in July and has been slowly converted into a staging point for the upcoming campaign to seize the city of Mosul, one of Islamic State’s last stronghold in Iraq.

The sprawling base once housed thousands of troops and numerous aircraft during the Iraq War, but after it was captured by Islamic State in 2014 it was systematically mined and its facilities destroyed. According to defense officials, the degraded state of the base has made it difficult to turn it into an effective staging area for the approaching Mosul battle.

Islamic State has used chemical weapons, in the past, most notably against Kurdish peshmerga positions in northern Iraq. The weapons, a mixture of mustard and chlorine agents, crudely loaded into a variety of artillery, mortar shells and rockets, have not been widely used.

The US-led coalition – in an attempt to stymie the group’s ability to make the weapons – has targeted individuals associated with overseeing their production and facilities where chemical ordnance is manufactured.