Brave Russian soldier wipes out band of ISIS fighters after calling in airstrikes on himself after being surrounded by jihadists
The U.S. military has killed numerous ISIS leaders in recent months. Earlier this month the Pentagon said it killed Omar al-Shishani, described as the Islamic State's 'minister of war', in an airstrike in Syria.
In November, the Pentagon said an airstrike in Libya killed Abu Nabil, another top ISIS leader.
The Iraqi army said Thursday its troops and allied militia had launched what is expected to be a long and difficult offensive to retake the second city of Mosul, ISIS's main hub in Iraq.
The army did not say how long this phase of the operation was expected to take and Iraqi forces still look far from being in a position to take the city itself.
The joint operations command is coordinating the battle by Iraqi security forces to retake the large parts of the country seized by ISIS during a lightning offensive in 2014.
It includes representatives from the US-led coalition that has provided air support, training and military advisers for the Iraqi army in its fightback.
Iraqi forces have scored important recent gains against ISIS, including by last month retaking Anbar provincial capital Ramadi.
But Mosul - which along with Raqqa in Syria is one of the jihadists' two main hubs - would be a major prize.
Experts have warned that any battle to retake the city will be difficult, given the significant number of jihadists and civilians in the city and the time ISIS has had to prepare defences.
Lieutenant General Sean MacFarland, the commander of the US-led operation against ISIS, has said that Iraqi generals do not think they will be able to recapture Mosul until the end of 2016 or early 2017 at the earliest.