Hundreds of heavily-armed ISIS militants launched a "significant" 17-hour assault on Kurdish forces in Iraq, a commander said Thursday as Defense Secretary Ash Carter continued his visit to the country.

 The fighters were eventually repelled with the help of U.S.-led airstrikes, according to Gen. Mark Odom, the most senior coalition officer in the area. It doesn't always end so well. The coordinated attack involved assaults on peshmerga forces in three locations to the north and east of the northern city of Mosul on Wednesday.

 Between 80 and 120 ISIS fighters took part in each assault, using vehicles with machine guns, truck bombs and suicide bombers.

 Defense Secretary Ash Carter arrived in Baghdad early Wednesday to meet troops and to talk with U.S. military commanders about the fight against ISIS. Which at this point no one knows will end.