An Iraqi military officer says
The officer with the anti-terrorism forces said Saturday that the attack occurred the night before in the Abar neighborhood, when the Islamic State fired a rocket loaded with chlorine. He said seven soldiers suffered breathing problems and were treated in a nearby field clinic.
The officer spoke on condition of anonymity as he was not authorized to release information.
U.S.-backed Iraqi forces are battling Islamic State militants in the more densely populated western half of Mosul. Iraqi officials say more than half of western Mosul has been retaken. The extremists were driven out of the eastern half of Mosul, Iraq's second-largest city, in January.