ISIS mounted a three-pronged attack on Wednesday night north and east of Mosul. Photo: Wikimedia Commons.

Islamic State fighters conducted their most significant military operation in northern Iraq in more than five months when they mounted a three-pronged attack on Wednesday night north and east of Mosul, American officials said Thursday.

The attack appeared to have been intended to show that the group is still a potent fighting force despite setbacks in Sinjar, Iraq, and in northern Syria. It may have also been intended to disrupt efforts by the American-led coalition to prepare for the eventual battle to retake Mosul, Iraq’s second-largest city, which was captured by the Islamic State in June 2014.

Read full story at The New York Times.