BAGHDAD — The spokesman for the Joint Operation Command in Iraq said Sunday that the Islamic State attacked government troops in western Mosul with a type of gas, the second such attack in as many days.

Brigadier General Yahya Rasool said six soldiers suffered breathing problems from the attack on Sunday and were treated in a field clinic. An investigation was launched to determine what type of gas was used.

The attack occurred a day after an Iraqi military officer said ISIS militants launched a gas attack in the al-Abar neighborhood in western Mosul.