Iraq launched an offensive to retake Mosul from the Islamic State group two weeks ago. Here is what we know so far about the country's biggest military operation in years:

Iraq's elite Rapid Response Division, which is now at the forefront of the southern advance on Mosul, has emerged as a key assault force in the country's war against jihadists.

As Iraqi forces backed by a U.S.-led coalition inch towards the Islamic State group in Mosul, experts and security sources warn that any assault on the jihadists' main Syrian stronghold of Raqa would be even more difficult.

For hardliners in Iran, running down the United States has become a lot easier during the U.S. election campaign -- it's just a matter of turning on the television.

Southeast Asia faces a growing risk of extremist violence as Islamic State group supporters increasingly work together, but law enforcement agencies are unprepared for the new threat, a report warned Tuesday. 

The notorious "Jungle" migrant camp on the outskirts of the French port of Calais has for years been a key staging post for migrants trying to smuggle across the Channel to Britain on lorries or trains.

The offensive to recapture Mosul from Islamic State jihadists has so far progressed faster than planners anticipated, but military experts fear the fighting could get tougher as U.S.-backed Iraqi forces enter the city.

Iraq's Christian community is one of the oldest in the world and the loss of what was once its largest town, Qaraqosh, to the Islamic State group two years ago was a major blow.

News that the town was poised to be recaptured from the jihadists sparked jubilation among Christians who had fled, with many dancing and singing in the city of Arbil.

Just three months after seeing off a failed coup, Turkish President Recep Tayyip Erdogan has put right back at the top of the agenda a plan to increase his powers through constitutional change.

The plan to create a presidential system means Turkey is likely to be heading to a referendum in the first half of next year, analysts say.

The battle for Mosul is a chance for President Barack Obama to claim an election-year victory over the Islamic State group in Iraq and offset failures in Syria.

Ask the White House about the slow motion catastrophe in Syria and, more likely than not, officials will talk about the different -- if related -- problem of the Islamic State group.