article_snippet: Iraqi troops and militia are battling to push ISIS back from the area with support from a US-led coalition and Iran.
article_snippet: But retaking Nineveh and Mosul poses a major challenge for Baghdad's forces, as the militants have had more than nine months to dig in.
article_snippet: Iraqi forces launched a huge operation last week aimed at retaking the city of Tikrit that, if successful, would serve as a stepping stone towards Mosul.